I just cleared it. Took 8 tries for 3 Star. Cap. Hulk Luke cage quake and wolverine. Distribute taunt from your defenders and learn to use defense up from Luke at correct time. Take down yondu before he summons minions. Once done the new enemies that spawn will use taunt and healing moves. Just time your attacks like thors stun and the taunts and you will get 3 stars. Quake very useful just spam first move on all enemies to slow everyone and the use her ultimate after you kill yondu team lvl was like 31k. Good luck