Find a checkpoint with Carusaurum nearby, such as this location on mission 5 (Screenshot). Collect the Carusaurum units, then select the "Restart from last checkpoint" option and collect them again. Play mission 14 under the Normal difficulty setting. Do a fast run only for Carusaurum units then replay the mission. This requires between five and seven minutes and results in 90 units of Carusaurum per run. A recommended loadout is Heavy Support, Rocket Hammer, Shield Guard, Sledge Hammer, Shadow Servant.