Here is the full list of all 27 Gear Up achievements.
Win 20 conquest rounds.
Destroy 1500 enemies
10 kills in a row
Back playing after more than one week of Gear Up absence.
Win 20 team deathmatch rounds.
Destroy 100 enemies
Destroy 75 enemies
Destroy 50 enemies
Recieve 500 damage without being destroyed in a round.
Win 20 deathmatch rounds.
Destroy 20 enemies with the Grayhound (saws).
Destroy 25 enemies
Win a TDM round overwhelmingly, with a ratio of 4:1 or higher.
Capture a conquest tower together with 3 or more teammates.
Destroy at least seven different opponents in a team game mode.
6 kills in a row
4 kills in a row
3 kills in a row
Destroy 10 enemies with the default starter cannon.
Repair 30000 armor in lifetime.
Win 3 conquest rounds.
2 kills in a row
Repair (1250) armor in one round of a team game mode.
Killed a deserting enemy
Assist in capturing at least 20 conquest towers in a single round.
Drown in the water at least once.
Win a Conquest round overwhelmingly, with a ratio of 4:1 or higher.