Iron Man resists being frozen to absolute zero:
http://s160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/?action=view¤t=ironmanabsolutezero.jpg
http://s160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/?action=view¤t=ironmanabsolutezero1.jpg
http://s160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/?action=view¤t=ironmanabsolutezero2.jpg
Destroys a mountain in a fight with Thing:
Iron Man claims he has "crushed dozens of world beaters":
Tony Stark resists the slave disc the Warbound have implanted on him and communicates with Dugan via his Extremis armor:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanarmorcommunication.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanarmorcommunication1.jpg
He reveals his plan for defeating the Hulk:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/negativezonetransporter.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/negativezonetransporter1.jpg
Even injured, slave - disced, and without his armor, Tony performs extremely well in the Hulk's gladiator games. He kills a giant monster from Sakaar and takes blows from Reed. He thenuses his Extremis interface to take control of one of the Warbound's robots:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/tonyvsmonster.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/tonyvsmonster1.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/tonyvsreed.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/tonyvsreed1.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/tonyextremis.jpg
His armor arrives fast enough to intercept gunfire:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanarmorspeed.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanarmorspeed1.jpg
He has organic armor built into his body as part of his Extremis powers, he also uses a chemical freezing weapon:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanorganicarmor.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmancapsule.jpg
Tricks Madame Hydra:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanintelligence.jpg
His armor's sensors are very advanced:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmansenses.jpg
They can even sense magic:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmansensesmagic.jpg
Owns an Asgardian and a vampire:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanvsroughhouse.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanvsbloodscream.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanvsbloodscream1.jpg
Defeat's Hydra's new weapon:
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanvshydracannon.jpg
http://i160.photobucket.com/albums/t173/EndlessMike9/Iron%20Man/ironmanvshydracannon1.jpg
Nice little strength feat here,
Iron Man grabs two tanks and smashes them together.
http://i94.photobucket.com/albums/l92/priest_85/img016.jpg
In another story set far in the future, Tony's body is dead, but his consciousness remains intact.
What's remarkable is, Tony found a way to send his consciousness across vast distances and merge it with 'hollow' IM vessels, animating them.
Also, should the IM vessel his consciousness is residing in at the time be destroyed, it will simply seek out one of the other IM vessels, [which are constantly being built], and merge with it.
Keep in mind, both of these actions occur instantly...
Here is, 'The End' Armor:
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Basically, short of destroying his consciousness, and all of the IM vessels at once, this Tony is unkillable.