Get a Beholder or an Angel and fly through levels so you can complete them faster. Then when you see a boss, just use their 2 damage skills(the one that reloads fast) to kill the bosses.
Btw why is it possible to lose all your unlocked characters and perks when deleting cookies? what if you buy that alchemist with kreds and losing it while deleted history? that would be really disappointing.
Wizard tip: If you find a spider queen, enslave it cuz it can summon permanent hatchlings! If you kept the 4 hatchlings and spider queen alive from current floor, you can have them all upto the next floor!
I have discovered a decent build. Necromancer with +4 on necromancer skill, +8 on focus and after that, put all skill points on Fortitude. Abuse Life Spike and Cannibalize since it kills enemies fast specially when stacked while it heals you decently. Also try to find items that adds physical defense(it will synergize better with your high hp than mage items) even it reduce your magic damage because you will barely use staffs when you can just attack enemy with Life Spike and regain ep using Cannibalize. With this build, i mostly get 1 damage only from archer and about half damage from melee units. Beware of mage units tho and stack Life spikes into them until they die or try to corner them and use a strong melee weapon to kill them. Also try to get warrior's book to get that skill with +1 hp per fortitude points. With this build, you just need bunch of ep mushrooms and almost no weapon required.
 "Chess Evolved Online"){kind=icon}
 "Soul Reapers"){kind=icon}
 "Great Dungeon in the Sky"){kind=icon}
 "Cardinal Quest 2"){kind=icon}
 "Rogue Fable II"){kind=icon}