Here is the full list of all 20 Chase achievements.
Win 5 games of any gamemode
Win 25 games of any gamemode
Win 50 games of any gamemode
Win 5 games in a team gamemode
Win 25 games in a team gamemode
Play 50 games of any gamemode
Steal the tracker from another player 50 times
Get 5 kills with the shield powerup
Get 5 kills with the black hole powerup
Kill 2 players with one black hole poweup
Kill 3 players with one black hole powerup
Kill 5 players with the pulse powerup
Steal the tracker from another player 5 times
Win a game of team death match with both players on the winning team not dying
Win a game of team last team standing with both players on the winning team not dying
Win a game of death match without dying
Win a game of last man standing without dying
Win a game of any gamemode against 3 bots
Win a game of any gamemode against 3 humans
Win a game of each game mode