In case you don’t know this. Electro has an ability where he reflects a portion of damage dealt back to the dealer. The higher the damage the higher the damage reflected back. Heimdall has a synergy where if you were to die once per fight he makes you indestructible and unstoppable for a few seconds.
Why I mention this?
Well Mangog has a node called Aggresion Fury which Increases attack by I think 50% every 2 seconds. Would building up enough Furies on the opponent then getting hit work on Mangog?
Btw I heard this works with an awakened quake via blocking
Here is an example of Aggresion Fury Heimdall Electro Cheese. You can try this out in Variant 2 Chapter 1 Quest 1. Go to the BlackBolt on the right