How can I defeat The Indomitable?

Of all of the bosses I've encountered in Desktop Dungeons, this guy seems like the most difficult. He only has about 200 hit points, but he has death protection of 50. That means that after I get him down to 1 hit point, I have to hit him 50 more times. And if I walk away, he heals back up. He also deals about 75 damage each time I attack. It doesn't seem like there are enough potions/level-ups/other healing possibilities to attack him that many times.

So how can I possibly defeat him? I've tried to think of ways to abuse poison or the monk's damage resistance to make it possible, but I've never even come close.

Update: The Indomitable has been rebalanced so that the first couple times you defeat him, he only has death protection of 20. I barely succeeded in beating that...

Solution 1:

There is some discussion on the forums, most of which is outdated, but the following post may be useful (source)

There are a handful of strategies (well actually, probably like 3 only) that you can use.

Halfling Monk worshipping Taurog.

Elf Sorcerer with Bear Mace.

But the most consistent is probably Elf Bloodmage (worshipping MA). Though when I say most consistent I mean relatively speaking.

The key preparations are probably Scout: Altar, Fireball Magnet and bank allowance. Anything else is definitely helpful but these are probably the ones you absolutely NEED.

Work your way to Mystera's alter, killing off as many Warlocks as you can and convert to her. Hopefully the altar should be close instead of across the map.

Turn on BludToPowaa and immediately start spamming fireballs and maybe Lemmisi to build piety.

Try to buy Flames as soon as you think it's a good time (when you're relying more on fireballs vs melee)

After that, at 90 piety, buy 5 "Magic" boons and then the "Weaken Magic resistance" boon, which will cover up the disadvantage of the former boon.

At level 8, start regen-fighting the boss. Toss all the fireballs you can at him until he's at 1 hp, uncover EXACTLY 3 tiles which will give you exactly the 6 MP you need to toss another fireball. The boss will recover 30 hp and the fireball will deal 32 damage, which will knock it back down to 1 and take off a death protection. Do this for as long as you possibly can until you exhausted all your tiles.

After that, use all your piety to buy Mana boons BUT not weaken magic resistance. Actual damage won't matter anymore and all you care at this point is to have maximum mana. Convert all your unneccesary stuff, quaff your mana potions, quaff you hp potions, buy more mana potions from shops, throw fireballs, buy more mana boons and hopefully you'll have enough fireballs to whittle down his 50 death protection.

To be honest, unless there's going to be more powerful preparations soon, I think this guy's death protection should be knocked down to like, 30 or something.

Also, note that your initial idea to use a monk does work, I linked to the story of someone who used life stealing as a monk to beat him.