This is an incredible card. So incredible that I feel it should be an auto-include in any ally-spam leadership deck where you're an Avenger hero. The allies you spam don't even need to be Avengers. They can be X-Men or Web Warriors or just a random assortment you collect.
I don't need to sing the praises of this card. It speaks for itself. You pay 1 card to draw 2 more. As long as you have an ally in play without one of these on it, it's pure value. Delayed a bit, yes. But value all the same.
What I really like about this card isn't how overpowered it is, but how it redefines Avengers tribal, giving it something it was sorely missing. That is, an actual mechanical identity.
When the game was first released, the Avengers tribal was a generic hodgepodge of different buffs with no cohesion or theme. It was the game's first team and needed this sort of generic feel. But times have changed and other tribes have developed their own identities.
Web Warriors benefit from swinging in and out of combat, with a focus on abilities when they enter play on the allies themselves, and letting you draw cards when they leave play through Web of Life and Destiny. X-Men tribal has a special focus on supports that want you in alter-ego like X-Mansion, Danger Room, Cerebro and Moira MacTaggert. This makes sense when you consider that X-Men stories focus a lot more on the school and the training that happens outside the battle than other teams do. X-Men are the alter-ego archetype to represent that side of them. The SHIELD archetype generally revolves around SHIELD Supports, with allies like Agent 13 and Dum Dum Dugan synergizing heavily with those supports, as well as cards like Sky-Destroyer which trigger off of any SHIELD card entering play. While other archetypes prioritize the Allies since they're superhero teams, SHIELD places just as much focus on the Supports.
Avengers tribal has always been a bit all over the place, though. It's been very generic without a clear identity of its own. And I think this fixes that. It takes Avengers from the generic team to being the "vengeance" team. An Avengers leadership tribal deck now plays allies at a discounted rate with Avengers Tower. It equips those allies with "Avenge Me!". When those allies are defeated, it lets you draw cards so you can actually avenge them with the new cards you draw.
Suddenly, Avengers have an identity that's uniquely their own. They're Avengers. They avenge the fallen. It's what they do.