4Game

May be slightly hard to explain how this NPC works but basically this NPC would provide you upgrades that stick with you even after death. These upgrades could consist of base health/stamina/eitr boost, double passives (belt + wishbone for example), forsaken power improvements (less cooldown and/or longer time), and/or permanent skills (sorta like how set bonuses work except it would be all skills with like maybe 5 or 10 and so on. Cap is still 100 to earn but these 10 would make it 110 for example.)

Now before anyone says this may be too OP, these upgrades would need to be mostly earned, not bought. For example, some would require rare item drops while some require boss drops, which encourages boss resummoning. Some would be progress locked as well. The biome this NPC spawns in could be plains anyways. Sorta think it could be an intelligent fuling but thats just my personal want. Could be another dwarf.