Special Conditions and checkup
Some attacks don't just deal damage — they leave the defending Pokémon Poisoned, Burned, Asleep, Paralyzed or Confused. These are Special Conditions, and they're where most beginner rules arguments come from.
Two facts cover almost everything:
That second half is the escape hatch. Any condition, however nasty, is one retreat away from gone.
The five conditions
Poisoned

Between turns, a Poisoned Pokémon takes 1 damage counter — 10 damage. It keeps happening every turn until it's cured or leaves the Active Spot. Poison never wears off by itself.
Haunter's Super Poison Breath does 30 and Poisons. That's really 40 by the time your opponent's next turn starts, and 50 by the one after.
Burned
Between turns, a Burned Pokémon takes 2 damage counters — 20 damage. Then flip a coin: heads and the Burn goes away, tails and it stays.
Asleep

An Asleep Pokémon cannot attack and cannot retreat. Between turns, flip a coin: heads and it wakes up, tails and it stays asleep.
Sleep is the harshest of the five, because the escape hatch is partly closed — you can't retreat out of it. You need a Switch-style card, an evolution, or a lucky flip.
Paralyzed

A Paralyzed Pokémon cannot attack and cannot retreat. No coin flip: it's removed at the checkup after the affected player's own turn. So Paralysis costs its victim exactly one turn — but that's often the turn that decides the game.
Confused
A Confused Pokémon can retreat, and can attack — but when it attacks, flip a coin first. Tails and the attack fails, and the Pokémon puts 30 damage on itself instead.
They stack — but only some of them
Pokémon Checkup
Between every turn there's a step called the Pokémon Checkup, where all of this resolves. It happens after one player's turn ends and before the next player's begins, and it applies to both players' Active Pokémon.
The order:
- Poison — 10 damage.
- Burn — 20 damage, then flip; heads removes it.
- Asleep — flip; heads wakes up.
- Paralyzed — removed, if the affected player has now had their turn.
Knock Outs from checkup damage are real Knock Outs: Prize cards get taken, and the player who lost the Pokémon promotes a new Active from their Bench.
Quick check
Your Active is Poisoned and Burned. Both players just finished a turn. How much damage does it take at the checkup, before any coin flips?
Last lesson: putting it together — knockouts, Prize trading, and how the game ends.