Use a champ that counters, or ideally reverses, regen. Are you doing a particular challenge, or just clearing a path?
Im doing the Carina challenge
Void is far and away the best option as he can reverse Diablo's healing consistently. Makes it a very easy fight.
Your light hits cycles icon. 3 icons
Your medium ender locks the icon.
Match the icon with Diablos icon.
Dash back hold block, now you are free to do whatever for 15 seconds.
It comes back after 15 seconds (grey timer on diablo).
Phase 2: There is a delay after you lock the icons, before you can do the dash back hold block.
Phase 3: It takes 3 seconds... to do dash back thingy.
….
All of that so you don't take 15% damage at the end of the timer every time.
…
With void. Use sp1 when you get it. Don't worry about hitting, try to do the matching game.
Diablo regens after sp1, dont hit him, let him drink and void will reverse it.
I’ve used a 5* void big boy boosts didn’t have a 6* or 7* it can be done look up on you tube
Void
How does one get to this point in the game and not have the answer to this question
Lots of players made it to valiant by just completing 8.3 with unit man and getting r3's with event rewards. It's surprisingly easy to stumble into the "end game" without knowing wtf you're doing.
https://forums.playcontestofchampions.com/en/discussion/comment/2866888?utm_source=community-share#Comment_2866888
Thank you. I didn't bring Void in my initial run of that challenge. And to answer you, ahmynuts, I'm a F2P player who only plays this game like 6 hours a week. I'm not a hardcore player. I don't spend every waking moment playing the game.
I did the fight with Warlock so he is an option too.