Ok here it is LMK

Iron Man
Army Buster
Cost 3
Avengers
Flight/Range
Atk:6
Def:6
Text:
As an aditional cost to recruit Iron Man Discard an Avenger Character card from your hand.

Discard an Avenger character card from your hand>Stun target army character with a cost less then the card you discarded.
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Iron Man
Tony Stark
Cost 5
Avengers
Flight/Range
Atk:7
Def:10
Text:
Iron Man gets plus 1 attack for every Avenger Character card in your Front Row.
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Iron Man
High Tech Warrior
Cost 7
Avengers
Flight/Range
Atk:16
Def:16
Text:
Whenever Ironman Stuns a defender Target player looses endurance Equil to the number of ready Avenger characters you control

Pretty cool and basically balanced. I think that the second ability should probably be "Once per turn."

Two things:

1) You need a sub name. As this is an anti-army card, it should be one of his more agressive incarnations.

2) You need to add the Avengers affiliation to the card.

How about this