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