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