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