I'm mostly done with a runthrough of War of the Chosen and, I have to admit, I didn't really have to cheat, just save scum a little, to deal with them. They're challenging but didn't feel unfair to me--each has a couple -strong- weaknesses that make dealing with them entertaining rather than frustrating. The Warlock, in particular, is a joke once you actually fight through his minions and get to him. I will admit, though, that once they're dead the game is dead easy since the Resistance groups are still helping you. My current game is literally just a matter of finishing some Avatar research and then the endgame.

I 110% agree with you, though, that the Viper King et al is far more frustrating than fun. Their react-to-everything bullshit is unbelievably aggravating and has no basis in logic. Did they take sprinting lessons from Jay Garrick? Mind you, there is one critical fact about them that they don't say in the manual that makes everything doable--they DO NOT HEAL between missions. You damage one and they will carry that wound until they eventually die. But...yeah. They're moronic. Almost as moronic as the armor you can make from their skins--GOD those things look stupid, even if they're powerful. It's amusing to see Vipers automatically panic on seeing the Viper Suit, though.

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Fearless creatures, we all learn to fight the Reaper
Can't defeat Her, so instead I'll have to be Her