Ruling miasma valley question

[aishen]

so yeah .. i was making a minefield .. and was confused with this situation:

suppose i already have beldum and two skarmory FB on field then i played miasma .. will they get affected even though they are already in the field? thanks in advance

 

[InfinityFangX]

They don't take 2 damage counters if you play the stadium after you've played your pokemon onto your bench.

Any Pokemon (You or Your Opponent) play onto your bench after you've played Miasma Valley (excluding Grass and Psychic) will take 2 Damage Counters.

 

[Shiftyenio]

and, if evolved in my bench any pokemon (excluding grass and psychic), take 2 damage counters?????

 

[PMJ]

No. Miasma Valley only triggers when you put a Pokemon onto your Bench from your hand.