To attach a Water Energy card from your hand to Suicune, you must discard an Energy card attached to Suicune. (Attach the Water Energy, and then discard an Energy card from Suicune.)
Attack 1:
[2W] Hypno Wave (30+)
Flip a coin. If heads, this attack does 30 damage plus 20 more damage. If tails, the Defending Pokémon is now Asleep.