The Mark XI (11), was the second Advanced Iron Man Suit, and was the eleventh suit created and built by Tony Stark, after the completion and successful tests on the Mark X, which was also an advanced Iron Man suit, as well as the first one built, sometime after the events of The Avengers.
It was featured in the movie Iron Man 3, and made it’s debut in the movie when Tony ordered J.A.R.V.I.S. to initiate the “House Party Protocol”, in which it was activated along with all the other suits to aid Tony in his battle against Aldrich Killian.
The Mark XI is the third armor to feature a new design on the face plate, as well as in it’s overall body armor.
The armor features a new design in the helmet and face plate. This new helmet design is in many new armors such as the Mark 17, 24, and 28.
The Mark XI also has powerful thrusters equipped on it’s back.