Once you've gotten the secret base level use a bear hug mine (left, right, down, Z)within range of the laser turrets, and when an enemy drives on the mine and gets stuck, if the turret is not destroyed it will shoot the enemy until he blows up or gets away severely damaged.
It's a little cheap so don't use it on a friend if you don't want to get hurt if he survives!
More tricks, tips and cheats for this game are right here - Vigilante 8 cheats
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