Go All Out has the potential to be the highest damage attack in the game, and its in leadership of all aspects!
The energy resource requirement is fine on a 2-cost card, but exhausting your hero as a cost means we need to compare the overall damage of this card versus the opportunity cost of missing a basic attack power. Generally the lower a hero's ATK and the higher their THW and DEF, the better this card will be for them.
Damage can obviously be increased using stat boosts. (Remember that ATK boosts would also increase a basic attack.)
- Symbiote Suit +3 damage while also being generally amazing by itself
- Adrenaline Rush +1 damage per copy discarded (but not better vs basic attack power)
- Civic Duty +1 damage per copy discarded
- Lead from the Front +2 damage per copy
- Morale Boost +3 damage per copy
- Moxie +3 damage per copy
- Avengers Assemble! +2 damage for an avenger hero
- Blaze of Glory +4 damage for a guardian hero
- Cloud 9 +1 damage for an aerial hero
- Armored Vest, Combat Training, and Heroic Intuition can all be played under the leadership player's control by another player and each gives +1
3 Damage Base: Ms. Marvel, Quicksilver
- Quicksilver +6 Maximum Velocity, +1 Accelerated Reflex, +1 Hyper Perception, +1 Reinforced Sinew
4 Damage Base: Adam Warlock, Drax, Hawkeye, Iron Man, Nova, Rocket Raccoon, Spider-Ham, Valkyrie, Wasp (tiny)
- Adam Warlock +1 Armored Vest, +1 Brute Force, +1 Combat Training, +1 Heroic Intuition, +2 Jarnbjorn trigger
- Drax +1 Drax's Knife, +1 per vengeance counter (max +3)
- Hawkeye +1 Hawkeye's Bow
- Rocket Raccoon +1 Cybernetic Skeleton, +1 Thruster Boots
- Spider-Ham +1 Huge Wooden Hammer, +1 Organic Webbing
- Valkyrie +1 Valkyrie's Spear, +1 Dragonfang (extra +1 vs enemy with Death-Glow)
- Wasp +1 Wasp's Helmet
5 Damage Base: Captain Marvel, Colossus, Doctor Strange, Spectrum (energy form included), Star-Lord, Thor, War Machine
- Captain Marvel +1 Captain Marvel's Helmet (extra +1 with Cosmic Flight as well)
- Colossus +1 Iron Will, +1 Titanium Muscles
- Doctor Strange +3 per copy of Magical Enhancements (max +6 total)
- Star-Lord +1 Leader of the Guardians
- Thor +1 Mjolnir
6 Damage Base: Ant-Man (tiny), Black Panther, Black Widow, Captain America, Gamora, Ghost-Spider, Groot, Hulk, Ironheart (version 1), Nebula, Shadowcat, She-Hulk, SP//dr Suit, Spider-Man (Miles Morales), Spider-Man (Peter Parker), Spider-Woman (including Superhuman Agility for playing the leadership card), Venom, Vision (Dense)
- Ant-Man +1 per Giant Strength (max 2) per form change (potentially infinite, but so is his basic attack)
- Black Widow +1 Synth-Suit
- Captain America +1 Captain America's Shield, +1 per Fearless Determination (max +2)
- Hulk +1 Boundless Rage
- Nebula +2 Unyielding Persistence
- She-Hulk +2 per Superhuman Strength (max +4)
- Spider-Woman +3 per other aspect card played Superhuman Agility (max +9), +1 per Brute Force (max +3), +1 Armored Vest OR +1 Combat Training OR +1 Heroic Intuition, +2 Jarnbjorn trigger
7 Damage Base: Ant-Man (giant), Ironheart (version 2), Wasp (giant)
- Ant-Man +1 per Giant Strength (max 2) per form change (potentially infinite, but so is his basic attack)
- Wasp +1 Wasp's Helmet
8 Damage Base: Ironheart (version 3)
Conclusions:
Averages 4 damage for 2 resources when taking into account missing a basic attack. This is not terribly impressive on the surface but it does scale exceedingly well with supporting cards.
Spider-Woman has the highest non-infinite damage potential, currently her magical Christmas land damage number can reach 58 damage, or 64 with Doctor Strange helping. The actual number would be a lot less but it is still possible to one-shot a villain stage without gimping the entire deck.
Ant-Man, Spectrum, and Wasp are all even better than they seem because they can very easily trigger Moxie.
Quicksilver was already using leadership for OTK combo plays and this leans even further into that.
Yet another reason Doctor Strange loves the leadership aspect, as it gives him high burst damage with his Magical Enhancements that he previously was not really using.
Finally, steer clear when using Venom because the opportunity cost needs to include not using his two Venom's Pistol on his basic attack. It is also exceptionally poor for Ms. Marvel who needs to give up her Morphogenetics.