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