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