Here is the full list of all 44 Chronicle: RuneScape Legends achievements.
Get every legend to at least level 25.
Have a weapon with at least 20 durability.
Have a weapon with at least 20 attack.
Win 500 games in any mode.
Have at least 10 base attack in a game.
Open 50 booster packs.
Get promoted to the gold league in ranked.
Win any game with Morvran.
Craft a card in the collection.
Win a least 3 games in a single dungeoneering run.
Open 10 booster packs.
Win any game with Ozan.
Have a weapon with at least 8 durability.
Have a weapon with at least 10 attack.
Win any game with Linza.
Win 50 games in any mode.
Gain rising star in ranked.
Have at least 30 gold in a game.
Win any game with Vanescula.
Start a dungeoneering run.
Build at least 3 custom decks.
Get promoted to the silver league in ranked.
Reach rank 1 in the ranked bronze league.
Complete a smithing skilling challenge.
Build a custom deck.
Complete a magic skilling challenge.
Complete an attack skilling challenge.
Complete the gold tier in solo.
Complete the silver tier in solo.
Draw at least 10 cards from effects in a game.
Open a booster pack.
Play 10 games in any mode.
Unlock all the Legends in the game.
Complete the bronze tier in solo.
Win any game with Ariane.
Win any game with The Raptor.
Have at least 5 base attack in a game.
Have at least 10 armour in a game.
Complete the tutorial.
Complete an entire dungeoneering run.
Get promoted to the diamond league in ranked.
Have at least 75 armour in a game.
Have at least 15 base attack in a game.
Have at least 150 gold in a game.