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