Selfdestruct causes damage. Your Pokémon faints upon using it.
If the attacker strikes first in the round and KOs itself as a result
of this attack, the enemy will completely lose the chance to do anything
that round. The next round will begin normally, and the opposing trainer
will have the option to choose an attack or switch out the enemy Pokémon,
Note that if the Pokémon that replaces the attacker also strikes first,
the attacking trainer will get at least two attacks in a row without
response. This is particularly important if the enemy was trying to use a
healing move at the time of the initial attack.
Other than the lost turn, the enemy will suffer no other detrimental
effects. It will not be charged a PP for the attack it didn't get to
use, and it will not be subject to recurrent poison, burn, or Leech Seed damage, since those penalties
are only enforced after the affected Pokémon attacks.
If Selfdestruct is used against a Pokémon that has created a Substitute, and this attack causes the sub
to break, the Selfdestructing Pokémon will not faint, as would normally be
the case. Its picture will no longer be visible, but it can continue to
fight normally. Note that this trick only works when the enemy
has put up a sub, not the attacker!
Because it is a Normal type attack, it cannot affect Ghost Pokémon.
While the Power of this attack has been rumored to be different in the
Colosseum2 mode of Pokémon Yellow, this is not true. Just another
* - We are aware that other sources report a different value, but
we arrived at this value based on in-game testing.