Sam brings a Remington Model 870 Shotgun when he and John/ Number 4 go to the conspiracy theorists's house to resque Henri, only to be told to stay in the car. The weapon changes hands several times before Henri empties it into a Mogadorian.
Number Six carries an M79 grenade launcher when she shows up at the school and discards it after firing the wepon's only round. The M79 fires a fictional energy grenade round.
Number Six carries a Lorian energy pistol which, since she's a good guy, fires blue energy rounds. She draws it after discarding her M79 and uses it for the duration of the battle in the school.
The Mogadorian's standard-issue weapon a a large assault rifle that, since they're bad guys, fire red energy bolts. The weapon seems to be partialy based off of a Mk. 46 machine gun and can fire semi-automatic or three-round bursts.
Some of the Mogadorians carry a smaller rifle which has the trigger unit concealed in a houseing they stick their hand into. Sam obtains one and later unhesitatingly blasts a Mogadorian.
While not stricly speaking weapons, the Commander's power cells for his heavy blaster as turned into improvised grenades by Number 4, obliterating the Commander and wrecking the football stadium.
A Mogadorian throws a fictional energy grenade at Number Six the school. In true Hollywood fation, the grende produces a massive fireball (red,of course) and throws Six twenty feet with no injuries.
