Here is the full list of all 22 Realm Royale Reforged achievements.
Loot Armor Potions 20 times.
Get a Crown Royale.
Win a match as a team of 4 without losing a single player.
Survive after becoming a chicken.
Eliminate an enemy player as a Warrior.
Get 50 eliminations as a Warrior.
Eliminate an enemy player as an Engineer.
Get 50 eliminations as an Engineer.
Eliminate an enemy player as an Assassin.
Get 50 eliminations as an Assassin.
Eliminate an enemy player as a Mage.
Get 50 eliminations as a Mage.
Eliminate an enemy player as a Hunter.
Get 50 eliminations as a Hunter.
Get 10 Crown Royales.
Forge 100 Items.
Get a Legendary Item in every slot.
Chicken a player from more than 800 feet away.
Get a Crown Royales with 3 different classes.
Eliminate an enemy player with your dagger.
Eliminate more than 10 players in a single match.
Forge your first Legendary Weapon.