So my Blackheart just respawned today and luckily,he was a scrapper.
EDIT: This strategy is really effective,but there is a new one much more effective than that and works for all classes. Potkettleblack explains it at the comments below.Totally recommend it.
Here's how i did it.
EDIT : Laser Spotter will also work.Targeted is prefered over Pinpoint Target but your bruiser will have a lot of extra crit chance from his buff so it shouldn't be a problem
2)You need Cyclops/Union Jack for the Flanked debuff.
3)The best bruiser for this fight is Hulk with his WW alt for the warbringer buff.If you have warbringer axe,you can also go for the avengers alt OR you can bring Juggy.
EDIT : Never mind,most bruisers work here,except Colossus and Thing,which are made for tanking.
(Prefered bruisers : Hulk,Juggernaut,Thor,She-Hulk,Captain Britain,Thundra)
Your agent has to have as many supporting items as possible in order to buff your bruiser
Try it out and tell me what you think guys!
P.S:My wiki editing skills suck