Introduction
Blackheart is one of the Marvel characters in Marvel vs Capcom 2. The son of Mephisto and (badly) seen in Ghostrider.
He's top tier and has one great zoning assist and a tricky ground assist. His infinite can kill anybody not paying attention.
Note that the Xbox 360 and PS3 versions of MvC2 have a variety of glitches involving Blackheart, such as his super sometimes doing no chip damage.
Colors
First row: LP, HP, A1. Second row: LK, HK, A2.
Moves
Special Moves
Inferno
hcb + p
The hp version tracks. Hits twice: once on the way up, once on the way down.
Dark Thunder
hcf + p
Super Moves
Armageddon
qcf + pp
Heart of Darkness
qcf + kk
Great chip damage. Ends in normal jump state. This means that if you get a flying screen, you cannot block momentarily on recovery. You can mash to get faster recovery if you don't want to eat an AHVB.
Judgment Day
qcb + pp
airok
Assist Types
Name
Damage
Cross-Over Combination
Alpha Counter
Notes
Dark Thunder Judgment Day
Dark Thunder Good for good control and for tricking people.
Inferno Heart of Darkness
Inferno One of the best assists in the game.
Standing 
Armageddon
Standing 
Strategy
Blackheart is skilled at occupying space through his demon normal moves; hitting fierce or roundhouse summons demons of varying effects. You can use those to keep the opponent busy while building meter and maintaining a lead.