Carnage (L), Venom, Spider-Man
a maxed out Carnage is still a dangerous thing against many, many World Bosses, not all, but most.
vs. Proxima Midnight: as long as you are careful this is an easy win. Only use Carnage's 6 and 3(ithink, the one that makes healing globs) and Team-up. If you have a decently built Carnage, and you are diligent about picking up healing globes, you should be fine. If you get caught in stun lock, as always team up and if you think you wont get out switch to Spider-man and use his 6 star to stay out of trouble until Team up is back or you think you can heal with Carnage
vs. Black Dwarf: I never use this team vs Black Dwarf due to its over reliance on physical and Black Dwarf's physical resisitance
vs Corvus Glaive: This is a dangerous team to chose, due to Corvus' proclivity to sitting in his own craters, meaning Carnage will be taking consistant damage when he attacks, but it is doable, mostly do to healing globes. The other danger is that Corvus summons minions who will step on your healing globes and take them away from you.
v. Super Giant: As normal, unless you get particularly unlucky with fear into standing in lasers, you should be fine, He seems to be immune to fear when he is using his 6 and 3 star attacks, but I could be wrong and have just gotten lucky with timing.
vs. Ebony Maw: I do not recommend this team here. Most of Carnage's Attacks have long animations, which will lead Ebony to iframe and many missed attacks. Also, his minions will cause you to waste some of your attacks on them, plus will eat up your healing globes.
vs. Thanos: Carnage team is a good choice here as he does not rely on buffs to do his damage. Solid fight, just make sure to switch if you are about to be hit for major damage and your globes are on cooldown
Goliath(L), Ant-Man, Yellowjacket
this team works the same for any of the bosses that you can use them on. It is mostly ant-man's 5 star, then team up, then ant-man's 5 star, then swap to either golaith or yellowjacket until it is ready to go again. You need to always have 1 cooldown 10% reduction striker (I prefer Yondu myself)
vs. Proxima: Good team choice, use above strategy
vs. Black Dwarf: This is primarily a physical team and BD is resistant to physical, not a team up I often use here.
vs. Corvus Glaive: Due to the need for dodge ignore strikers, I will not often use this team as my dodge ignore strikers are not that buff. When I did not have as diverse of a roster I would use this team but it would often get down to the last minute before I won. Do able, just not easy
vs. Super Giant: easy win. Goliath is great for stripping down her energy shield she puts up. Just be careful of the usual and you are fine
vs. Ebony Maw: Rough fight as Ebony can cancel your 5 star skill by using an iframe of his own. This does not happen as often if you wait to start the chain after Ebony has used one of his own iframe attacks
vs. Thanos: You will not get to use Ant-Man's buff for that long as it will be stripped from you. If you have him t2 it will happen less, but this team works fairly well as they are mobile and have a lot of iframes, make sure to switch ant-man out when third wave starts, you dont want to lose your main attacker due to bad luck
