Cryomancer
Arcane
magic system, especially demon summoning. It can literally kill you, or worse.
Hellfire warlocks on 3.5e could lose control over his summoned demon.
I like low magic games like the Witcher, Gothic/Risen etc
Witcher has elves, mutants, monster hunters, sorcerers... And Gothic has Gods literally interfering in the real world. You have cities ruled black magicians, chosen one of Gods, fire mages that can make rain fire... Gothic is mid magic.
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I remember when I saw a guy who adapted 5e into low magic settings. There are a lot of changes.
- Only clerics and warlocks. Clerics channel the power of Gods. Warlocks bargain with outsider forces for knowledge. Magic is not a mundane thing, so no Wizards or Druids.
- No spell slots, instead casting a spell deals CON damage to the caster equal to the spell level and it requires a long rest to heal.
- You start as a lv 0 commoner, martial class levels are easy to get but to get a level of cleric, you need to take vows and do the tests in a church. To level as a warlock, you need to summon your patron and bargain with him for knowledge. No good patrons exist and the price can be gold, slaves, memory(which reduces your WIS score).
- After few levels as a cleric(5), the cleric needs to talk to the high priest for promotion challenges
- Warlocks needs to bargain for knowledge after each level up and there are tables and rolls for each level up.
- A lot of spells got changed and can critically fail and a fireball can explore in your own hands for eg.
- Magical items, including scrolls and wands are 20x more expensive.