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