Here is the full list of all 58 Paladins achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Have over 30 different champions at mastery level 20 or higher
Reach Master in Ranked
Have over 30 different champions at mastery level 15 or higher
Earn over 500,000 Gold over your play history
Earn over 1,000,000 Gold over your play history
Play over 300 matches
Have a Paladins account over 1 year old
Spend over 100,000 Credits in the item store over all your matches
Shield over 200,000 damage in a match
Heal over 100,000 health in a match
Get a daily reward 7 days in a row
Unlock Ranked
Have over 30 different champions at mastery level 10 or higher
Build your own custom loadout
Reach a 20 kill streak in a match
Play 250 hours with a player from your friends list in your party.
400 Double Kills.
Play 100 hours with a player from your friends list in your party.
200 Double Kills.
Be the only player alive in a match.
Reach level 30 during the Paladins Beta.
Kill an enemy player who is on a 15 killstreak or higher.
Kill a player in the air who is over 100 units above the ground.
Get a killing blow after the round has ended.
Die to an environmental hazard.
Deal more than 100,000 damage during a match.
Unlock 100 Cards.
Kill an enemy player while you are at or below 50 Health.
Kill a player with an environmental hazard.
Kill an enemy player from over 300 units away.
100 Double Kills
Play 25 hours with a player from your friends list in your party.
10 Champions at Mastery 5.
9 Champions at Mastery 5.
8 Champions at Mastery 5.
Play 100 matches while in a party.
7 Champions at Mastery 5.
Land 5 headshots in a row without missing.
6 Champions at Mastery 5.
50 Double Kills.
5 Champions at Mastery 5.
4 Champions at Mastery 5.
Play 10 hours with a player from your friends list in your party.
Play 50 matches while in a party.
3 Champions at Mastery 5.
Play 5 hours with a player from your friends list in your party.
2 Champions at Mastery 5.
Kill more than 20 enemy champions in a single match.
10 Double Kills.
Play 20 matches while in a party.
Deal damage to every enemy champion in a match before any of them damage you.
Play 10 matches while in a party.
1 Champion at Mastery 5.
Kill an enemy champion after they had already killed you.
Win a match where the enemy team scored no points.
Survive more than 50 battles with less than 10% health.
Play a match while in a party.
Complete the Paladins Tutorial.