The Current Meta

(Stats/number are from powers at 5 cover lv 270 from their character treads)

Gamora is a unique character in a sense that she is one of a few characters who can produce both attack and strike tiles by themselves, so she benefits from those strike tiles very quickly. It may not be a big deal in PvE since you have two other seats to choose from, but this is big in PvP when you essentially pick two and better if they both are boosted.

I don't think the passive on her black is that good. But the active part which make 6 attack or strike tiles are great. I don't have the numbers at hand, but that's probably one of the higher ones in term of special tile strength per ap ratio.

Nova's black cost 8 while Gamora's black cost 9. In the end you need to make 3 3-matches to use either of them. Speed-wise, they are identical to me. Exceptions are a rare case is when you can make 2 4-matches right away for Nova and when you use boosts.

Gamora also produce purple special tiles which is not her color. This is probably a small point, but it lets you keep collect ap and fire her power easier than Nova whose tiles are black. For Nova, you can either run him 5/5/3 and produce less amount and less beefy tiles, or stick with 5 black and risk having to match those tiles.

Gamora's red has a fine print on it. Her countdown procs at the end of your turn, so essentially this power deal 6227 per 10 ap from the first turn (as long as you are not unlucky that the move you make wipes the cd tile). 623 damage per ap is not bad, more on an average for 4* which can also double-dip strike tiles right away.

Gamora's blue. 3-turn stun for 6 ap is definitely spectacular. I think this one is better than Nova red. The first reason is, collecting another 6 blue ap within 3 turns is much more doable than 6 more red ap in two turns. So you can stun-lock the last opponent much easier. the second reason is, for strike/attack tiles meta, stunned enemies still take damage while airbourned do not which works better with her other two powers.

Lastly, their kill-move. Both Gamora and Nova has this one in common; produce enough tiles, and sacrifice them all for massive damage. Nova removes all friendly black strike tiles and deal 8119 damage for 8 ap which is not that good due to current power-creep these days. More and more characters can deal that much damage straight out of the box. But when you need it, it is still a good finish-the-match move and is easily executed. Gamora also removes all purple strike and attack tiles to insta-kill the enemy. Sadly, this power is not reliable since sometimes it procs at a wrong time or you cannot proc it when you need it.