Customize a mech so the weapons on-board in an online game to look like the following:
ER-Laser ER-Laser Mgun LRM-5 LRM-5
The first LRM-5 will be duplicated between the second LRM-5, and take up no mass or critical. It will be invisible but do damage when fired and create heat. Note: You have to be in "chain fire" mode. The weapons can be changed, but the number of weapons must be uneven and the final weapon must be on the right side of your mech.