Mechanics [Gen 4] Snatch should only deduct Pressure PP if successful

[Cazenovia]

What type of bug are you reporting? Mechanics

What is the bug?
In Gens 3 and 4, Snatch is erroneously removing 2 PP if it successfully snatches and uses another move instead of just a single PP.

Are you able to replicate it? If so, how?
PS! Replay

 

[Hydrametr0nice]

Hey, I think that is the expected behavior and it is a visual bug. There is a test called [Gen 4] should deduct additional PP from Snatch if the Snatch was successful. Unless you have tested it in the cartridge and the test is wrong.

 

[Cazenovia]

Hey, I think that is the expected behavior and it is a visual bug. There is a test called [Gen 4] should deduct additional PP from Snatch if the Snatch was successful. Unless you have tested it in the cartridge and the test is wrong.

From my reading of the test, it seems like that test is designed for testing only the Snatch interaction with Pressure - at least on my HeartGold cartridge Snatch only uses 1 PP if it successfully snatches a move (cart footage).

 

[Hydrametr0nice]

You're right.
https://github.com/smogon/pokemon-showdown/pull/11575

 

[Cazenovia]

You're right.
https://github.com/smogon/pokemon-showdown/pull/11575

Sorry if this changes your PR, but doing a bit more testing into it I found a different bug relating to Snatch and Pressure - currently on PS!, if Snatch successfully snatches a move used by a Pressure mon that fails (such as Recover at full HP), then it will only deduct 1 PP (PS! Replay), however on cartridge Snatch will still be deducted 2 PP (cart footage).

EDIT: Did a bit more testing and found a glitch I don't think has ever been documented - if Snatch is used against a Pressure mon and snatches a move that fails, Snatch will be deducted 2 PP, HOWEVER if the very next turn the Pokemon switches out, Snatch regains one of its PP (cart footage). To be clear, this is not a visual bug - if using Snatch under these conditions results in Snatch's PP reaching 0, then the Pokemon will be unable to use Snatch unless it switches out the very next turn, in which case it will have 1 PP left that can be used (cart footage). This glitch does not occur if the move that is snatched from the Pressure mon succeeds with Substitute (cart footage), but does work with at least Recover (see above) and Harden (cart footage).

EDIT 2: I also tested it without the Snatcher having Recover as well (that's for another bug I'm still collecting footage on) to make sure that that wasn't what was causing the glitch and got the same results (cart footage).

 

[Hydrametr0nice]

Sorry if this changes your PR, but doing a bit more testing into it I found a different bug relating to Snatch and Pressure - currently on PS!, if Snatch successfully snatches a move used by a Pressure mon that fails (such as Recover at full HP), then it will only deduct 1 PP (PS! Replay), however on cartridge Snatch will still be deducted 2 PP (cart footage).

(EDIT: Don't make any changes yet - I found a super weird behaviour that I need to test a bit more before being certain)

I tested the following (and is coherent with my PR):

• Successfully snatched Calm Mind → -2 PP
• Failed to snatch Water Gun → -1 PP
• Successfully snatched Light Screen and Light Screen succeeded → -2 PP
• Successfully snatched Light Screen and Light Screen failed → -2 PP

Pressure deducts PP if Snatch successfully steals a move, but the stolen move doesn't need to succeed.

 

[Hydrametr0nice]

Sorry if this changes your PR, but doing a bit more testing into it I found a different bug relating to Snatch and Pressure - currently on PS!, if Snatch successfully snatches a move used by a Pressure mon that fails (such as Recover at full HP), then it will only deduct 1 PP (PS! Replay), however on cartridge Snatch will still be deducted 2 PP (cart footage).

EDIT: Did a bit more testing and found a glitch I don't think anyone has ever been documented - if Snatch is used against a Pressure mon and snatches a move that fails, Snatch will be deducted 2 PP, HOWEVER if the very next turn the Pokemon switches out, Snatch regains one of its PP (cart footage). To be clear, this is not a visual bug - if using Snatch under these conditions results in Snatch's PP reaching 0, then the Pokemon will be unable to use Snatch unless it switches out the very next turn, in which case it will have 1 PP left that can be used (cart footage). This glitch does not occur if the move that is snatched from the Pressure mon succeeds (cart footage).

1. Is there any interaction if a Pokémon snatches a move from the partner of a Pokémon with Pressure? What if both opponents have Pressure?
2. What happens if Snatch had 1 PP initially? Does it recover that PP after switching out?
3. What if there is a turn in between before switching out? For example, turn 1 uses Snatch and the move fails, turn 2 get put to sleep before is able to act, turn 3 switches out.
4. The one above can also be tested by a Pokémon with Truant (turn 1 uses Snatch, turn 2 fails to move, turn 3 switches out).
5. Does this glitch happen in Gen 3?

I can test all of them except the 1st and 3rd when I get home, if needed.

 

[Cazenovia]

Is there any interaction if a Pokémon snatches a move from the partner of a Pokémon with Pressure?

Snatch loses 1 PP as normal.

What if both opponents have Pressure?

Snatch loses 2 PP as normal.

What happens if Snatch had 1 PP initially? Does it recover that PP after switching out?

Snatch will not recover that PP after it switches out.

What if there is a turn in between before switching out? For example, turn 1 uses Snatch and the move fails, turn 2 get put to sleep before is able to act, turn 3 switches out.

Snatch will have lost 2 PP after switching back in.

Does this glitch happen in Gen 3?

Would take me a bit to set this up but I can test it later today.

 

[Hydrametr0nice]

Snatch loses 1 PP as normal.

Snatch loses 2 PP as normal.

The first two need to be re-implemented. I'm assuming Pressure also activates if it snatches an ally's move.
Edit:
What if the Pokémon switches out using U-turn?
What If the target faints before or after acting the following turn?
(Sorry for all the questions I can test them later today too)

 

[Cazenovia]

I'm assuming Pressure also activates if it snatches an ally's move.

Correct, and the PP glitch is still possible by snatching an ally's move. (will need to do more research; the glitch was still performed there even though Harden was used successfully, maybe only certain moves cause the glitch to happen??)

What if the Pokémon switches out using U-turn?

Snatch loses 2 PP.

What If the target faints before or after acting the following turn?

The glitch still works if the target faints before the following turn, I believe it should still work after the following turn too.

Does this glitch happen in Gen 3?

It does not.

 

[Hydrametr0nice]

The glitch still works if the target faints before the following turn, I believe it should still work after the following turn too.

I wanted to know if the glitch still happens when the Snatching Pokémon faints. I know there's no Revival Blessing in Gen 4, so it's mostly insignificant, but it might tell us something about when the trigger occurs.

I tested it, and if the Snatching Pokémon faints before it moves on the next turn, the glitch doesn't activate. I'd just like to know whether the glitch occurs if the Snatching Pokémon faints on the same turn it steals the move. I can't test this one on my own.

 

[Cazenovia]

I wanted to know if the glitch still happens when the Snatching Pokémon faints. I know there's no Revival Blessing in Gen 4, so it's mostly insignificant, but it might tell us something about when the trigger occurs.

The glitch does not happen if the Snatching Pokemon faints the same turn that snatch is used. I've been testing what moves work with the glitch and which don't, will post something in the past gens research thread sometime soon.

 

[Hydrametr0nice]

The glitch does not happen if the Snatching Pokemon faints the same turn that snatch is used. I've been testing what moves work with the glitch and which don't, will post something in the past gens research thread sometime soon.

Don't all snatchable moves that can fail activate the glitch? If not, I'll mark the PR as ready and implement the glitch another time.

 

[Cazenovia]

Don't all snatchable moves that can fail activate the glitch? If not, I'll mark the PR as ready and implement the glitch another time.

Nope, for some reason there are 7 moves that I've tested (Belly Drum, Camouflage, Charge, Focus Energy, Ingrain, Stockpile, Substitute) that don't work with the glitch - there could possibly be more as I didn't test every single move but I tested everything that wasn't a simple stat boosting or recovery move.

 

[Hydrametr0nice]

Do you want the bad news? The extra PP deduction also seems to occur with Counter, Mirror Coat and Magic Coat, only when they succeed. I haven't tested the glitch.

Other moves that might behave the same way include Assist, Copy Cat, Me First and Sleep Talk. I've already confirmed that Metronome always deducts only 1 PP.

Edit: This was after one successful execution and one unsuccessful execution of each move.

 

[Hydrametr0nice]

Magic Coat seems to always deduct 1 PP in Gen 5, but Mirror Coat (and probably Counter) deducts 2 PP when it connects. We need to find out if this happens for all gens.
Edit: in Gen 9, Counter and Mirror Coat still deduct 2 PP if used against a Pressure Pokémon, but 1 PP if they fail.

 

[Cazenovia]

Do you want the bad news? The extra PP deduction also seems to occur with Counter, Mirror Coat and Magic Coat, only when they succeed. I haven't tested the glitch.

Other moves that might behave the same way include Assist, Copy Cat, Me First and Sleep Talk. I've already confirmed that Metronome always deducts only 1 PP.

Edit: This was after one successful execution and one unsuccessful execution of each move.

This glitch also seems to occur for Counter (presumably Mirror Coat too) and Magic Coat and does not occur for Me First (deducts 2 PP), Sleep Talk, Copycat, Assist (all deduct 1 PP).