Ace's Manga Rare variant (OP-05) has reached nearly $1,600
Too many really
Naturally, there are far too many of these varied and often interesting abilities to cover here but theres likely an Energy card for just about any situation you may need it for
For example, when Boon-Bringer Valkyrie enters the battlefield, you can either put a +1/+1 counter on Boon-Bringer Valkyrie itself, or you can put a +1/+1 counter on another creature and have that creature gain flying, first strike, and lifelink until end of turn
Sunset Saboteur feels like it has the potential to be a defining card that is simultaneously worth building around and can fit in a wide range of decks
While it is expensive and somewhat slow, if you can untap with it on the battlefield and a grip full of cycling cards, the game should quickly get out of hand, despite the randomness inherent in Unpredictable Cyclone