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