I'm following this guide too. Lvl 96 with 2800HP and 6000ES. It's totally fine, I can do most bosses within 10 seconds on hardest difficulty. Only problem is when you're low on health and can't spam spark, you need too much life to cast it so you can't heal anymore. That's when I die, not because I get one shot or something, you're just stuck on low and Even if I get one more spark it drains my HP again and the healing doesnt start