Galacta
Each turn, the first card you play at another location reveals
with +2 Power.
Gwenpool
On Reveal: Pick a random character in your hand 3 times. Give +2 Power each time.
Mirage
On Reveal: Copy the character that costs the least from your opponent's hand into your hand. Give it +2 Power.
Nebula
Each turn your opponent doesn't play a card here, +2 Power. (except the turn you play this)
Peni Parker
On Reveal: Add SP//dr to your hand.
When this merges, you get
+1 Energy next turn.
Rocket and Groot
Moveable once.
After your opponent plays a card here, steal 1 Power from it.
Speed
Ongoing: +1 Power for each turn in which you spent all your Energy.