                     ---- Repel Mechanics ----
0) Encounter Slots

1) Encounter Rate
1.1) White Flute and Bike
1.2) Illuminate / Arena Trap / No Guard

2) Repel effects and calculation

3) Special Abilities effects
3.1) Static / Magnet Pull
3.2) Hustle / Pressure / Vital Spirit (APEV method)
3.3) Cute Charm & Synchonize

4) More calculations (to show Repel 

5) Various particular cases
5.1) Feebas, Swarms, GBA Insertions
5.2) Great Marsh and Safari Zone
5.3) Honey Trees and Radar Hunting
5.4) Pass Powers


                      How do Repel works ?



-------0) Encounter Slots

To clearly understand Repel's effects, and how to calculate the remaining Pokemon percentage, the encounters mechanics have to be explained first.



In order to easily put Pokemon in routes, game designers created boards, with a fixed number of lines and columns.
Each column is assignated with a percentage, a Pokemon, and a level (which makes 3 lines).
The number of columns depends on the type of encounters you're doing :
12 for walking encounters
5 for surfing
5 for fishing (or a number depending on the road in 3rd gen)

Also, the percentages linked to the columns don't change regadless of where you are doing encounters, which means that if you know the Pokemon put into the columns, you will instantly know their percentage.

These boards are also called encounter slots (because on each column or slot, you write a Pokemon and its level).


The percentages distributions on encounter slots are like this :

Walking :
Column Number : 00 - 01 - 02 - 03 - 04 - 05 - 06 - 07 - 08 - 09 - 10 - 11
Percentage :    20 - 20 - 10 - 10 - 10 - 10 - 05 - 05 - 04 - 04 - 01 - 01

HgSs Safari Zone :
Column Number : 00 - 01 - 02 - 03 - 04 - 05 - 06 - 07 - 08 - 09
Percentage :    10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10

Surfing :
Column Number : 00 - 01 - 02 - 03 - 04
Percentage :    60 - 30 - 05 - 04 - 01

DP, Old Rod Fishing :
Column Number : 00 - 01 - 02 - 03 - 04
Percentage :    60 - 30 - 05 - 04 - 01

3rd Gen Super Rod + DPPt Good/Super Rod  + 5th Gen Fishing :
Column Number : 00 - 01 - 02 - 03 - 04
Percentage :    40 - 40 - 05 - 04 - 01

HgSs Fishing :
Column Number : 00 - 01 - 02 - 03 - 04
Percentage :    40 - 30 - 15 - 10 - 05

3rd Gen Old Rod Fishing :
Column Number : 00 - 01
Percentage :    70 - 30

3rd Gen Good Rod Fishing :
Column Number : 00 - 01 - 02
Percentage :    60 - 20 - 20

Rock smashing :
Column Number : 00 - 01 - 02 - 03 - 04
Percentage :    60 - 30 - 05 - 04 - 01


Headbutt and Honey Trees are a little bit different, so they will be mentioned later.




And the "classic" percentages you can find on sites like serebii/bulbapedia are sums of all the percentages of the columns where a same Pokemon name is found.
But if a Pokemon can be found at different levels, you won't know the % of the Pokemon for each level, which is THE main factor for Repel Tricking.

There are sites listing encounter slots, and their links are given in "Useful links" file, along with a little application displaying encounter slots and calculating Repel Tricks.

Events like Swarms, GBA Inserts, Day/Night appearances, Pokeradar exclusives, Trophy Garden Pokemon, Great Marsh, HgSs Safari ZOne, also depend on these Encounter slots.
For example, GBA Insert Pokemon replace the Pokemon in slots 08 and 09 (the 4% slots), whereas Swarm Pokemon replace the Pokemon in slots 00 and 01 (in 4th gen only).
Introducting different Pokemon or % is all about changing the Pokemon in encounter slots (the level of the slot doesn't change, except for HgSs Safari Zone)(3rd and 5th gen swarms work slightly differently, but well, Mechanics are full of exceptions).









--------1) Encounter Rate


But for now, we only know encounter slots, so let's try to make a Pokemon appear.
For this, the game also stores values depending on routes and methods, who determine the frequency of encounters.
For example, surfing has a lower encounter rate than walking, and White Forest has a higher Encounter Rate than the usual grass areas.

This encounter rate can be changed depending on certain conditions.
-Encounter Rate drops :
Riding a bike (x4/5)
Using Black Flute (x1/2) (Doesn't work on 5th Gen)
1st Pokemon holding Cleanse Tag (x2/3)
1st Pokemon having Stench / White Smoke / Sand Veil + sandstorm (x1/2)

-Encounter Rate boosts :
Using White Flute (x2) (Doesn't work on 5th Gen)
1st Pokemon having Illuminate / Arena Trap / No Guard (x2)
Using Encounter Pass Power

1st Pokemon having Sticky Hold / Suction Cups (Emerald/Hg/Ss/5th Gen Fishing only)



And every step or movement(turning) you make on grass, water,... the game generates a random number, and compares it to the encounter rate.
If the random number is less than the encounter rate, an encounter occurs.

Then, another random number is picked, and the game uses it to determine which Encounter Slot will be chosen (the probability for choosing a certain encounter slot are the percentage linked to them).

And then poof, a wild battle occurs.








---------2) Repel effects and calculation


Now that we know the global way of making encounters, we will add Repel onto this algorithm, along with some special abilities.

The concerned abilities are :
Static / Magnet Pull / Pressure, Hustle, Vital Spirit (same effect) / Intimidate, Keen Eye

(Cute Charm and Synchronize will also be mentioned, because they have an effect on Pokemon generation.)



 At first, Repel doesn't work anywhere, and with anything.
Repel won't work if you're :
Fishing
Checking a Honey Tree
Headbutting a Tree
using Sweet Scent
using Rock Smash in gen 4
battling a set Pokemon (legendary, Sudowoodo in HgSs, Kecleon in RS,...)
going into a shaking Patch with pokeradar


If Repel's effect is still on, then, when the game will try to make an encounter, it will compare the level of the chosen Pokemon (picked on a certain encounter slot) to the 1st Pokemon of the party that is alive, and 
if the wild Pokemon has a lower level, then the encounter won't be made.
In other words, every encounter of lower levelled Pokemon (than your first Pokemon alive) will be prevented.
This means that you can reduce the number of encounter slots who will bring an encounter.



    The application are linked to mathematics, so here is a little example :
Route X, Repel Lv 25
Slot 00 : Lv 25 Pidgey (20%)
Slot 07 : Lv 26 Rattata (5%)
All other slots : Lv 24 Spearow (75% in total)


Only 20+5 = 25% of the starting Pokemon will be encountered, which means that encountes will be a bit slower, but also that on these 25% of Pokemon who will appear, there are 20% of Pidgey, and 5% of Rattata.
So if you were to encounter a Pokemon with this Repel, you would have 20/25 = 4/5 = 80% chances of encountering a Pidgey, and 5/25 = 1/5 = 20% chances of encountering a Rattata.


If you wanted to find a Shiny Pidgey, your chances that, if a Shiny were to appear, it would be your target have gone from 20% to 80% !!
Encounters may be slower, but you have greater chances to fall onto your targetted Pokemon, and this is a more important factor in Shinyhunting (will be detailled below).

On this Route, you also can Repel at Lv 26 to only leave the 5% Lv 26 Rattata, to encounter 100% of Rattata.


Now, we can generalize this result, and calculate Repel's effect on % on any zone like this :



Final % of a Pokemon = A / B

A = Sum of the % of the remaining Pokemon Encounter slots (the ones not repelled)
B = Sum of the % of all the remaining Encounter slots


Note : For Surfings, Encounter slots can have Level spreads (ex : from Lv 20 to Lv 35), and the formula will be :
A = Sum [ % of remaining Pokemon Encounter Slot x remaining number of Lv of the encounter slot / (Max Lv of the slot - Min Lv of the Slot + 1) ]

B = Sum [ % of remaining Encounter Slot x remaining number of Lv of the encounter slot / (Max Lv of the slot - Min Lv of the Slot + 1) ]













----------3) Special Abilities effects






Now, let's talk about Special Abilities' effect :



Intimidate, Keen Eye :

Intimidate and Keen Eye act like Repel, but will have 50% chances to be activated when a battle is generated, and repel Pokemon at a Lv lower than "Lv of first alive Pokemon" minus 5.
Unfortunately, these abilities are not really useful in Repel Tricking (instead of saving money for not using Repel, but giving less interesting results in terms of % of targets).






---------3.1) Static / Magnet Pull


Static, Magnet Pull :

These abilities have 50% chances to be activated when a battle is generated.
If they are activated, then the game will select all the encounter slots containing an Electrik (Electrik for Static or Steel for Magnet Pull) typed Pokemon, and will randomly select one of these encounter slots to make the encounter.
Thus, the % of the slots won't be considered in the process, and only the number of Encounter slots containing Electrik (or Steel for Magnet Pull) typed Pokemon has interest.

Because these abilities' effect takes place during the Encounter Slot selection,  they can be stacked with Repel.

The formula is a little more complicated than just using Repel :

Final % of a Pokemon = A/(2xB) + C/(2xD)

A = Sum of the % of the remaining Pokemon Encounter slots (the ones not repelled)
B = Sum of the % of all the remaining Encounter slots
C = Number of remaining Encounter slots of the Pokemon (if he's Electrik-typed for Static, or Steel-typed for Magnet Pull)
D = Number of remaining encounter slots of Electrik (or Steel) typed Pokemon


There is a 1/2 factor because Static / Magnet Pull has 1/2 chance to activate.










---------3.2) Hustle / Pressure / Vital Spirit (APEV method)


Hustle, Pressure, Vital Spirit : (also named APEV (in French) or HPVS (in English, but less cool) )

These abilities have 50% chances to be activated when a battle is generated.
If they are activated, then the game will look at the generated Pokemon, then look at all the encounter slots (of the area) containing this Pokemon, and make a battle selecting an encounter slot  giving the higher level at the generated Pokemon.
In other terms, the game picks an encounter slot, then, if the ability is activated, it will make an encounter with another encounter slot, this slot containing the same Pokemon as the first chosen slot, but with the maximal level possible.


Here is another example :
Route X, Repel Lv 25
Slot 00 : Lv 25 Pidgey (20%)
Slot 01 : Lv 19 Rattata (20%)
Slot 07 : Lv 26 Rattata (5%)
All other slots : Lv 24 Spearow (45% in total)


At Lv 25, only slots 00 and 07 are left, giving me :
Total % : 20% + 5% = 25%
Pidgey : 20/25 = 0.8 = 80%
Rattata : 5/25 = 0.2 = 20%
Spearow : 0/25 = 0%

But now, I will also use APEV with Repel (I could have said Pressure, but I like APEV).

--APEV doens't Works : 1/2 chance
Gives 80% Pidgey , 20% Rattata


--APEV works : 1/2 chance
Here, there is a single Pidgey slot, and all Spearow slots are Repelled, so nothing will change for these Pokemon.
But if the game chose at first the 01 Slot, the 20% Rattata slot, then it would do an encounter with a Rattata coming from Slot 07, because this slot contains the best level for Rattata in the area.

Thus, instead of only seeing Slot 00 and Slot 07, each time Slot 01 Pokemon will be selected, it will be able to "appear", disguised as a Slot 07 Pokemon.

The % will then be :
Total % : 20% + 5% + 20% = 25%
Pidgey : 20/45 = 4/9 = 44.44%
Rattata : (5+20)/45 = 5/9 = 55.56%

Here, we could use the Pokemon of the 01 Slot even if their level was below the Repel Lv, because there was a non Repelled slot that contained the same Pokemon.


And to conclude our example, the global % of Pokemon will be :
Total % : 1/2 x 25% + 1/2 x 45% = 35%
Pidgey : 1/2 x 80% + 1/2 x 44.44% = 62.22%
Rattata : 1/2 x 20% + 1/2 x 55.56% = 37.78%


So, we successfully were able to increase the rate of Rattata for a Lv 25 Repel, which is one of the two benefits of the APEV method.




You will understand the other benefit with another calculation.

Same Route, Repel Lv 26
Total % : 5%
Pidgey : 0%
Rattata : 5/5 = 100%
Spearow : 0%


Let's use APEV :

1/2 chance APEV don't work :
Total % : 5%
Gives 100% Spearow

1/2 chance
Total % : 5% + 20%
Gives 100% Spearow

Global effect of APEV :
Total % : 1/2 x 5% + 1/2 x 25% = 15%
Rattata : 1/2 x 100% + 1/2 x 100% = 100%


The % of remaining Pokemon tripled, which is a boost more important than Illuminate. Furthermore, Repel Tricks with low total % of remaining Pokemon increase the needed time to make an encounter, so it is in general liked to increases the encounter rate, or this % in order to decrease time needed to make encounters.

These decreases of frequency aren't fully described by the total % of remaining Pokemon, so if you want to make an idea of how it is, I think it would be better to try for yourself.





Now, let's write the whole formula :

Total % of remaining Pokemon : B + D/2
Final % of a Pokemon = (A + C)/(B + D/2)


A = Sum of the % of the remaining Pokemon Encounter slots (the ones not repelled)
B = Sum of the % of all the remaining Encounter slots
C = Sum of the % of the Repelled Pokemon Encounter slots (if the Pokemon still appears with Repel)
D = Sum of the % of all the Repelled Encounter slots (if the Encounter Slot Pokemon still appears with Repel)









----------------3.3) Cute Charm & Synchonize


Synchronize :

Synchronize activates 50% of the time.
When Synchronize is activated, the wild Pokemon's nature will be the nature of the Synchronizer.




Cute Charm :
Activates 66.67% of the time (2/3 chances).
When Cute Charm activates :
if the Wild Pokemon can be Male or Female, it sex will be the opposite of the Cute Charmer's Sex.
if the Wild Pokemon can only be Male, Female, or has no Sex, nothing happens.

In 4th gen only, Game designers changed Cute Charm mechanics (since its effect existed in Emerald), and to force the Male / Female appearance if Cute Charm is activated, they forced the game to give the Wild Pokemon a PID within 25 possible value (only depending on the forced Sex, and the Sex Ratio, the chances the Wild Pokemon have to be Male or Female, ex : 25% M /75% F , 50% M / 75% F,...).

(The PID, or Pokemon Identification number, is a huge value (between 0 and 4294967295 that determines characteristics of the Pokemon, with its Shininess).


This choice of 25 possible PID totally ruins the chances of falling on a Shiny Pokemon if Cute Charm activates, because these 25 PID will always be the same if  you encounter Pokemon that has the same sex Ratio, and if your Cute Charm Pokemon has the same sex, and because Shininess is determined by a formula that combines the Pokemon's PID and your ID and SID.
So if you don't have some particular combinations of ID and SID (in general, this will never happen, but you can use cheats to make it true), no Shiny will appear when Cute Charm will activate and have an effet.


So, in normal times, there will only be 33.33% of the wild Pokemon that will be able to be Shiny with Cute Charm (1/24.576 to fall on a Shiny).
BUT, if you were to be on a zone with Pokemon that aren't affected with Cute Charm, then things get different.
Because only the Pokemon affected by Cute Charm will see their chances of being Shiny divided by 3, whereas the others will stay at 1/8.192.



This means that you can increase the % of finding a only Male, only Female, not Sexuated Shiny Pokemon by reducing the chances of falling on a Shiny sexuated Pokemon.
Because like this, if you were to fell on a Shiny, il would be more likely to be a non sexuated Pokemon.
So, Cute Charm will not change the global % of encountering Pokemon, but the % of a determined Pokemon to be Shiny.



Which means more mathematical formulas, and some cool searches, because it can be combined with Repel pretty well !

Be aware that using Cute Charm will decrease your chances of finding a Shiny Pokemon. It may not be a high decrease (like 1/9.200), but there is one.





Cute Charm % calculations :

For a zone that would have non-sexuated Pokemon (one or more).

If the Pokemon isn't affected by Cute Charm :
E = 3xA / (100 + 2B) = A x B' / B
B' = 3*B / (100 + 2B)

Chances to find a Shiny Pokemon = (8.192x3x100)/(100+2xB)

With :
E = Chances that if a Shiny is encountered, it will be this Pokemon
A = % of the Pokemon (Repel calculations included)
B = % of all the Pokemon unaffected bu Cute Charm (Repel calculations included)

B' = Chances that if a Shiny is encountered, it will be a Pokemon unaffected by Cute Charm

(B and B' are percentages, ex : B = 50%, not B=0.5, else the results will be wrong)


If the Pokemon is affected by Cute Charm :
E = Ax(100-B')/(100-B)
B' = 3*B / (100 + 2B)










---------4) More Calculations


As you may have already seen, probabilities matters a lot into Shiny Hunting, and I would like to introduce a new point of view about % of targets in hunts.


Because lots of people that aren't really fond about Repel Tricking argue that is it better to keep hunting fast than increasing the % of the target.
As for myself, I would like to make another calculation that shows the interest of increasing the % of the target.



So, let's take a target with a probability to appear of X

Every calculation here will be made without percentages, which means that X = 100*X % (ex : 0.2 = 100*0.2 % = 20%).


I have a probability of 1-X to not find my target.

And I will calculate the probability to not find my target with a certain number of Shinies.
This probability equals (1-X)^n, with n the number of Shinies.

Unfortunately, I can't put any plot into these files, so I will use some examples to show some things.


   X = 0.05 = 1/20 =  5%

Chances to not fall on the target with :
1 Shiny : 95%
2 Shinies : 90.25%
3 Shinies : 85.73%
4 Shinies : 81.45%
5 Shinies : 77.38%
6 Shinies : 73.51%
7 Shinies : 69.83%
8 Shinies : 66.34%
9 Shinies : 63.02%
10 Shinies : 59.88%
15 Shinies : 46.33%
20 Shinies : 35.85%
30 Shinies : 21.46%
40 Shinies : 12.85%
44 Shinies : 10.47%



   X = 0.1 = 1/10 = 10%

Chances to not fall on the target with :
1 Shiny : 90%
2 Shinies : 87%
3 Shinies : 72.9%
4 Shinies : 65.61%
5 Shinies : 59.05%
6 Shinies : 53.14%
7 Shinies : 47.83%
8 Shinies : 43.05%
9 Shinies : 38.74%
10 Shinies : 34.87%
15 Shinies : 20.59%
20 Shinies : 12.16%
21 Shinies : 10.94 %



   X = 0.2 = 1/5 = 20%

Chances to not fall on the target with :
1 Shiny : 80%
2 Shinies : 64%
3 Shinies : 51.2%
4 Shinies : 40.96%
5 Shinies : 32.77%
6 Shinies : 26.21%
7 Shinies : 20.97%
8 Shinies : 16.78%
9 Shinies : 13.42%
10 Shinies : 10.74%


   X = 0.3 = 3/10 = 30%

Chances to not fall on the target with :
1 Shiny : 70%
2 Shinies : 49%
3 Shinies : 34.3%
4 Shinies : 24.01%
5 Shinies : 16.81%
6 Shinies : 11.76%
7 Shinies : 8.23%
10 Shinies : 2.82%



   X = 0.4 = 2/5 = 40%

Chances to not fall on the target with :
1 Shiny : 60%
2 Shinies : 36%
3 Shinies : 21.6%
4 Shinies : 12.96%
5 Shinies : 7.78%
10 Shinies : 0.60%



   X = 0.5 = 1/2 = 50%

Chances to not fall on the target with :
1 Shiny : 50%
2 Shinies : 25%
3 Shinies : 12.5%
4 Shinies : 6.25%
10 Shinies : 0.09%



   X = 0.6 = 3/5 = 60%

Chances to not fall on the target with :
1 Shiny : 40%
2 Shinies : 16%
3 Shinies : 6.4%
10 Shinies : 0.01%



Here, I tried to find the number of Shinies that would give me ~10% chances to not find my target, and here are the results :
X = 0.05, n = 44
X = 0.1,  n = 21
X = 0.2,  n = 10
X = 0.3,  n =  6
X = 0.4,  n =  4
X = 0.5,  n =  3
X = 0.6,  n = < 3

For ~20% chances to not find my target
X = 0.05, n = 30
X = 0.1,  n = 15
X = 0.2,  n =  7
X = 0.3,  n =  4
X = 0.4,  n =  3
X = 0.5,  n =  2
X = 0.6,  n = < 2

For ~30% chances to not find my target
X = 0.05, n = 23
X = 0.1,  n = 11
X = 0.2,  n =  5
X = 0.3,  n =  3
X = 0.4,  n =  2
X = 0.5,  n = < 2
X = 0.6,  n = << 2


We can see important changes between probabilities of 0.05, 0.1, 0.2, and 0.3 (and even 0.4).
And if you take a look at the searches in the files and at the basic % in serebii/bulbapedia, you will see that lots them increase at least a Pokemon percentage from 10% to 20%, or 20% to 30%, or 5% to more than 10%.



And a search with a target at 10% / 20% is a search where you can be certain that you will have to find more than one shiny to obtain your target, which is why I calculated the % to not find your target for a certain number of shinies.

 There were some hunters that (for example) chose to hunt a 20% target, instead of increasing its percentage to 30% or 40%, and that found 5,6 or even 9 Shinies before their target.
It is clear that using Repel Trick slows you down a little bit, but if you calculate your encounter speed while using a mid-strong Repel Trick (40% remaining Pokemon or more), you will find that it is more than half the normal speed (because the duration of every battle doesn't change, and Illuminate + White Flute highly boost the Encounter Rate).
So if you calculate the theorical time needed to find a 20% target in 9 Shinies Without Repel, or to find a 30%  target in 5 Shinies With a mid-strong Repel, you will find that it would be at most equal, or else advantageous for the Repel strategy (because the less Shinies you find, the less your average number of encounters per Shiny will be near 1/8.192).
Furthermore, not using Repel will only give you 4 unwanted Shinies, that could be pretty useless because you gathered the whole fammily or dislike them.

And this is just a study of the searches where Repel can hardly increase the % of the target, because there is also lots of searches that increases the % of the target to more than 40%, sometimes up to 66.67%, 75%, 80%, or 100%. (The Radar Hunting will give you 60%-70% of your target for every search), so in these cases, Repel would be a really interesting option.


Here ends my calculations on Repel Tricking effectiveness over a single target search.




Because the difference between Repel and Routes is that Repel will in most cases  make one or two Pokemon proeminent, diminishing the % of the others, which is why Routes keep a certain interest if nearly all of the Pokemon they have match your likings.










--------5) Various Particular cases

If you want more details on actual slots on areas, check Angeflo's Encounter Calculator, or Dragonflycave.
Here, I'm detailling some mechanics, as well as every modification linked to encounter slots.




-Repel in 2nd Gen
It is possible, but Repel wasn't designed for Repel Tricking, so even a sligh Repel takes tons of times.
This is a reason why I didn't translate my work on GSC : lots of the searches are reaally long (but they would be cool on emulator instead).



-Rock-Smashing Repel
You can do it in RSE/Fg/Lg, to hunt Nosepass, Graveler (with its FrLg asewome sprite) or Magcargo.



-Fishing Feebas
In RSEDPPt, if you fish on some squares on certain areas (Route 119 for RSE), you can find Feebas.
They have 50% chances to appear with every Rod (Old Rod being faster in RSE), and the rest of the time, normal Pokemon appear (with half their basic percentage, because half of the time, a Feebas appear).



-3rg and 5th Gen Swarms
Instead of replacing the Pokemon of the Slots 00 and 01 like in 4th Gen, the Swarming Pokemon are put in another encounter slot (made of a single column), and this single encounter slot has 50% in 3rd Gen / 40% in 4th Gen chances to be picked, whereas any other encounter slot (the usual 12 encounter slots) have their chances to be selected multiplied by 0.5 in 3rd Gen / 0.6 in 5th Gen.
Calculation of Repel percentages for 5th Gen Swarms goes like surfs (with Lv going from 15 to 55).



--Radar Hunting
This is a really powerful method !
See DPPt Comments



--Great Marsh Binocular Pokemon
For each zone (there are 6 of them), the Binocular Pokemon takes Slots 06 and 07 (both at 5%)
See DPPt Comments



--Trophy Garden Pokemon
1st Trophy Garden Pokemon takes Slot 07, and 2nd Trophy Garden Pokemon takes Slot 06 (both at 5%)
See DP Repel List



--GBA Insertions
GBA Insertions Pokemon take slots 08 and 09 (both at 4%)
See DP/Pt Repel List, or Comments




--Honey Trees
You have to use Honey on a Tree to maybe attract a Pokemon.
Honey Trees contain Encounter Slots, who are linked with a certain manner.

There are 4 out of the 21 Trees that can contain a Munchlax (Munchlax Trees), and they depend on your ID and SID (see Useful Links and Angeflo's Encounter Calculator to have a Munchlax Tree calculator).

Once a tree is slathered, a Pokemon is generated, and a timer is launched.
6 hours after the slathering, and for 18 hours, you will be able to meet the Pokemon in the tree.
There is 10% chance (9% on a Munchlax Tree) that no Pokemon will be generated.
If this is the case, when wou will examine the Tree just after slathering it, it will say "There is a sweet scent in the air...", which is also said when you doesn't slather any Honey on a tree, and you will be able to re-slather the tree to try generating a Pokemon.

When a Pokemon is in a tree and can be encountered, the Honey Tree is shaking.
This can indicate (more or less precisely) if the Pokemon in the tree is rare or not (it would only help to find Munchlax) by the force of the Shaking.
But this isn't a good indicator, since a common Pokemon can also induce a strong shaking.


Here are the percentages for generating Pokemon in Honey Trees :

DP Normal Tree :
29% Wurmple
22% COmbee
14% Silcoon / Cascoon
11% Burmy
7.5% Cherubi
5.5% Aipom
1% Heracross

10% No Pokemon


DP Munchlax Tree :
32% Combee
16% Burmy
15% Cherubi
11.5% Wurmple
8% Aipom
4% Silcoon / Cascoon
3.5% Heracross
1% Munchlax

9% No Pokemon


Pt Normal Tree :
32% Combee
14% Wurmple
22% Burmy
11% Cherubi
10% Aipom
1% Heracross

10% No Pokemon


Pt Munchlax Tree :
32% Burmy
22% Combee
16% Cherubi
12.5% Aipom
4% Wurmple
3.5% Heracross
1% Munchlax

9% No Pokemon

Also, if you slather a tree immediatly after fighting a Pokemon in this same tree, the percentages of Pokemon will change, because they are issued from a combination of two encounter slots, and in this case, you will have 90% chances that the newly generated Pokemon will be in the same encounter slot than the previous.
To prevent this, you have to go to another Honey Tree (to slather Honey or fight its Pokemon) after fighting with a Honey tree Pokemon, instead of re-slathering it directly if it doesn't contains your target Pokemon.

Once you find your target, you can save near the tree and soft reset its Pokemon to hunt it.




--Hoenn/Sinnoh Radio
These Pokemon take Slots 02 to 05 (the four 10% slots)



--HgSs Safari Zone
Each Zone has 10 Slots with 10% for each.
At first, each slot contains "Normal" Pokemon from Safari Zone, with levels going from 14 to 17.
Then, once blocks are unlocked, each slot can be replaced by a "Block" Slot, with other Pokemon at other levels (around Lv30-40).
Some Surfing and fishing slots can also be replaced (with less interest for fishing, as they can't be repelled).
Some replacements require high quantities of blocks, that can only be attained by placing the area, and waiting a certain amount of days, because each block can count for 2,3 or 4 blocks of the same specie depending on how long the area has been installed.

See HgSs comments for all slots for every zone and blocks requirements.




--Pass Powers
Encounter Pass Power increases your Encounter Rate, being very useful in slow searches (like Cryogonal or Evee).

In BW2, there is also a Lucky Pass Power that changes the % of Encounter slots.

Here are the changes (Thanks for MaitreArmand, Angeflo, Boubar86, and Shasseur66 for their work)

Walking :
Column Number : 00 - 01 - 02 - 03 - 04 - 05 - 06 - 07 - 08 - 09 - 10 - 11
Percentage :    20 - 20 - 10 - 10 - 10 - 10 - 05 - 05 - 04 - 04 - 01 - 01
Lucky + :       10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 05 - 05 - 05 - 05
Lucky ++ :      05 - 05 - 05 - 05 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10
Lucky +++ :     01 - 01 - 04 - 04 - 05 - 10 - 10 - 10 - 10 - 10 - 20 - 20

Surfing :
Column Number : 00 - 01 - 02 - 03 - 04
Percentage :    60 - 30 - 05 - 04 - 01
Lucky + :       50 - 30 - 10 - 05 - 05
Lucky ++ :      40 - 30 - 10 - 10 - 10
Lucky +++ :     30 - 20 - 10 - 20 - 20

Fishing :
Column Number : 00 - 01 - 02 - 03 - 04
Percentage :    40 - 40 - 15 - 04 - 01
Lucky + :       40 - 35 - 15 - 05 - 05
Lucky ++ :      30 - 30 - 20 - 10 - 10
Lucky +++ :     20 - 20 - 20 - 20 - 20
