Here is the full list of all 25 Diablo IV achievements.
Reach Level 100 with any character.
Kill the most challenging Echo of Lilith.
Upgrade your Healing Potion to max tier.
Complete a Sacred and Ancestral Nightmare Dungeon.
Reach Level 50 with a Hardcore character.
Collect 1000 Aberrant Cinder in Helltide zones.
Imprint 10 items at the Occultist with an Aspect from the Codex of Power.
Craft any Elixir and any Incense.
Explore all of Estuar.
Kill any World Boss.
Reach Level 50 with any character.
Acquire 10 Caches of Chaos from the Tree of Whispers.
Complete the campaign.
Kill 666 Bandits, Cultists, or Knights.
Upgrade a piece of Armor, Jewelry, and a Weapon.
Kill 666 Ghosts, Skeletons, or Zombies.
Get 5 PvP kills.
Kill 50 enemies in melee range and 50 enemies out of melee range as a Rogue.
Kill 50 enemies in Werebear form and 50 enemies in Werewolf form as a Druid.
Kill 666 Drowned, Vampires, or Werewolves.
Kill 50 enemies while Berserking as a Barbarian.
Kill 666 Snakes or Spiders.
Summon 100 Skeleton Mages or Warriors as a Necromancer.
Kill 666 Demons, Fallen, or Goatmen.
Kill 100 enemies with Fire, Frost, or Lightning damage as a Sorcerer.