primary fire: fire nails at a rate of 20 nails per second. holds 100 nails before needing to recharge nails from this variant deal more damage than other nails.
alt fire: shoot a magnet (max three at a time) that will attract nails to it before exploding acting as a grenade.

primary fire: fire nails at a rate of 25 nails per second this variant can shoot unlimited nails but will shoot slower the more heat it has (shown by a yellow bar on the nailgun)
alt fire: after building up heat use one of two heatsinks to spray a ton of heated nails that can light enemies on fire (62.5 nails/sec)

fire nails at a rate of 12.5 nails per second when untethered and 25 per second when tethered, There is no limit to nails.
alt fire: attack a cable to an enemy and pump electricity into it. after five seconds killing the enemy with the cable attached will create a chain of electicity that can kill many small enemies (like filth all at once)

magnets can be used to attract rockets magnets can also be used to lower the radius of a stalker explosion
all nails can be attracted to magnets including an overheat burst of nails to create a much bigger nailbomb putting more magnets in the same spot will increase the amount of nails it can hold.
if electicity is used in water the damage and radius of the electic blast will be increased greatly. at the cost of damaging v1 if it's in the water.