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