Skirmish

Looking for Skirmisher, a group of Kig-yar shock troops introduced in Halo: Reach?

Skirmish is a game mode in Halo Wars and Halo Wars 2. Skirmish serves as the Halo Wars equivalent of Custom games, allowing players to alter game settings, activate Skulls and play against custom teams of human or AI players in any map or gamemode.

Halo Wars
Skirmish in Halo Wars is the default mode of play for multiplayer. In this mode, players start with limited Supplies and must built units and research upgrades manually. In Halo Wars 2, this mode was renamed to Deathmatch.

Halo Wars 2
Skirmish returns in Halo Wars 2 as custom games-only, with the gametype renamed to Deathmatch. However, Halo Wars 2 skirmish mode allows for much greater match customisation than Halo Wars. Players can choose to activate or deactivate the Fog of War, increase or decrease how many Resources players start with among other options.