PokéBase - Pokémon Q&A
6 votes

"When a Pokémon with this Ability is hit by a move that makes contact, there is now a 30% chance that the attacking Pokémon will become poisoned, paralyzed or asleep: there is a 9% chance of poison, 10% chance of paralysis, and 11% chance of sleep."

This is a direct quote from the Bulbapedia page for Effect Spore.

My question is, would a steel type like Corviknight still have a 30% chance to activate effect spore? And if so, would the poison chance still occur 9% of the time without working? Or would effect spore's odds change and have something like a 15% chance to paralyze and a 15% chance to sleep? Do we know the odds for this?

And my secondary question, for combo types, like magneton or toxtricity, would they then have a 30% chance to get slept?

If it's part-Steel-type or part-Poison-type, Poisoning won't occur. If it's part-Electric-type, Paralysis won't occur.

1 Answer

3 votes

Read up on what Marty from Smogon has to say about it. He's the research leader for Pokemon Showdown, his job is to study battle mechanics in an actual Pokemon game and replicate how they work for Showdown to make it an accurate emulator.

Basically, Effect Spore will activate 30% of the time. So if a Pokemon makes contact with an Effect Spore mon, the game rolls a dice with 100 values. If the dice lands in the first 30 values effect spore will activate, but it uses that same value to pick the status. This works differently in gen 5 due to a coding error, causing skewed odds, but in all other games it's essentially 1/3. To get sleep, it's the first 10 values (1-10, 0-10^), paralysis the next 10 (10-19, 11-20^) and poison is the last 10 (20-29 or 21-29^). If the game rolls, say, a 23 for poison and the Pokemon is either a poison/steel type or has Immunity, the effect of Effect Spore does not roll again for paralysis/sleep. So the probability in the game is unaffected.

^roll in gen 5

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