In the Team Deathmatch, teams must kill the maximum number of enemy Mechs over multiple Rounds.
In 5v5 Deathmatch mode, two full Teams compete for kills over multiple Rounds. You can unlock it through the Progress Path by accumulating 1400 XP.
The Team that destroys more Mechs in 2 minutes wins the Round, and the Team that wins 2 Rounds first wins the Battle. You can also win a Round by destroying every Mech on the enemy Team.
If the 2 minute timer runs out and both Teams have the same number of kills, you will get 30 more seconds of Overtime. If both Teams still have the same number of kills at the end of Overtime, the Round will be a draw.
MVP Medals are awarded to Mechs that have the greatest impact on the overall Battle. This includes performance from all Rounds, if a Mech is used by a player more than once.
See also: Why did one player receive 2 MVP rewards?