• Bunch of luck
  
• Classic "Heaven" Difficult

- Choose "Flex"

• Monster Bonus^3 - Perfect "curse". This way you don't have to worry about the amount of pips on the monsters' cubes
  
• Level up - Helps with the first levels (I skipped all the level 4 lvl-ups because they were terrible)
  
• Hunt^1 - Even such a small increase in damage helped me.
  
  Other top blessings:
  
  • Boss Smash^99
    
  • Monster Hp Down^*
    
  • Extra Rolls^*
    
  • Hunt^2
    
  • Hunt^3
    
  
  
• Damaged Monsters - Helps with some bosses such as "Sarcophagus" etc. In my opinion one of the most useful blessings. It also helps to gain pips for Bloodlust
  
  
• Lucky Start - Small bonus
  
• Boss Smash^1 - Small bonus for boss figths

!!! IMPORTANT !!!

Turn on 'Myriad offers" in options!!!

• Coffin - gives you a new hero
  
• Warlock - gives you a powerful spell for "one-shot"
  
• Agent - two sides with "Quad-use" and two funny sides. Nice combo with "Collar"

• Collar (Yellow hero with top/bottom damage sides + Collar + Agent)
  
• Olympian Trident
  
• Charge Link - for managain
  
• Ogre Blood - for managain
  
• Lichfinger - for managain. (Warlock + Lichfinger + Damaged Monsters + Charge Link on other managain-hero)

I wouldn’t recommend this achievement for beginners. It’s more suited for those who have experience in the game but still haven’t been able to beat it.

You can build a team around infinite(many) cantrips.
The cantrip-based build has one main problem: Ghosts and Shades.
Ideally, a stray dagger shouldn’t hit them, as that will make them impossible to kill later. Of course, you might get a blessing that grants Fierce on all sides, but that’s extremely rare, although it’s very powerful. With this blessing, you could even try to achieve the “no kills” dungeon completion achievement, which means you wouldn’t need to pick Hunt^3. However, unfortunately, this guide isn’t about that :)
If you have a well-established hero combination, you can safely skip some upgrades until level three. For example, you might not want to upgrade the Bard to a Poet, because the Poet doesn’t have cantrips, and if you’ve gathered items to boost cantrips on your Bard, it’s better to keep him at that level.

Feel free to ask any questions about the tactics, and I’ll answer them in the comments.