Quest Global Node:
Two normal combos (MLLLM) normally give the opponent a little bit above 1 bar of power. So, if you can do this, you will have a bar of power to use before the end of your combo.
A half combo (MLL or MLM) or a Heavy to give them a bit more power.
Then 1 more combo.
The final thing to remember is that if the combo-ending hit is the one that pushes the opponent over a bar of power, then you get a bar of power because of the node, you cannot use that special because you will use it too late and they will block it (or you can use someone like HB, Valkyrie, Massacre who benefits from their special attacks being blocked.)
Don't Do This!
How I did it.
DOs and DON'Ts of Power Struggle:
Superior Iron Man -> Falcon -> Sabretooth -> Venom -> She-Hulk -> OML -> Winter Soldier -> Crossbones (Boss)