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