Heimdall is the most expensive non-variable-cost card printed. Most characters will need to dump their entire hand just to play him in alter-ego form, to the exclusion of other cards that turn. Not every hero can afford this luxury, and sometimes when you draw him you simply will need to do something else (especially when under Shadow of the Past or expert mode pressure).

The response is absolutely ridiculous in solo play or duo with a stunned villain, choosing the villain's boost card and your next encounter card, but is much more lukewarm in larger games where it will usually only affect the order of boosts.

However, what we have in this card is probably the first ally that you absolutely do not want to use to defend. His 8 threat thwarted over 4 turns is simply unparalleled in a single card, essentially twice as potent as an empowered For Justice!. Moreover you can decide to use his last point of health to instead throw a Haymaker. The flexibility might not rival Nick Fury, but the longevity certainly does, especially when you consider that this investment is worth supporting with other cards such as the ever- amazing First Aid.

In summary, don't write this card off because it is hard to use effectively. It isn't as flashy as Energy Channel or Shield Toss, but in this game that forces constant decisions about opportunity cost, the payoff can certainly be found here.

Unfortunately, this card in my opinion is horribly overpriced.

What do you want to get from it: negate next attack.

Baring some exceptions (Rhino with Charge or Bulldozer) you can use ally with 1 hp to do just the same, except an ally will do something before that - Mockingbird will stun the enemy and thwart/deal damage (for the same price), Nick Fury costs 1 more but will give you back most of his cost, the list goes on and on, but in my opinion, the more cost 3 or less allies we get, the even worse this card will become.

TL;DR: if you think of using it, don't, flood your deck with cheap allies instead

I'm looking forward to trying this card out (the card has not been released yet at the point of writing). The ability to ignore the consequential damage when an ally attacks or thwarts, particularly if you were planning on doing so with your hero anyway, is strong in itself, particularly for the more expensive allies. But when you consider the ability this has for getting around the weaknesses of some allies (looking at Wonder Man and Lockjaw in particular for now, but I'm sure there will be others that will benefit from this going forward).

Hercules is capable of dealing 12 damage (3 dmg x 4 health). If you have one minion engaged, that's 5 for 12. Two minions, 4 for 12. Three minions, 3 for 12. Needless to say, these are insane numbers. Hercules is a great target for: Inspired (in multiplayer), making Inspired a 1 cost, deal 4 damage or thwart 4. Honorary Avenger would be a 1 cost, deal 3 damage. And even heavily incentivizes the use of First Aid - making it a 1 cost, deal 6 damage and Med Team (in multiplayer), making it a 3 cost, deal 18 damage.

As far as future proofing goes; any card that boosts the HP of an Ally will improve the efficiency of Hercules, with the goal of playing him only once and keeping him on the field for the rest of the game.

I've seen debates on the pros/cons of "Power of" cards. When looking at leadership; all allies cost 2 or more resources to play. As more Leadership allies are added to the game, PoL only cements itself further as a must-have card in any ally-related leadership deck. It can be used for Make the Call or as payment for resource-specific cards due to the wild resource it provides - a significant advantage to all Heroes and against all Villains.