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