Energo weapon

An energo weapon is a melee weapon that uses energon to power a shaped energy field that significantly enhances the cutting and blunt-impact properties of the weapon. When the fuel cell is consumed, the weapon can still be used at its "normal" potency.

Blitzwing's electron scimitar operates on the same principle and is also energon-powered, but the mechanism differs.

Let's just face it: The Dinobots like to kill things. They like it a lot. And they like to get up close and personal when doing it. But there are times when teeth and tail just won't cut it. When that time comes, the Dinobots will typically use their energo-swords.

Except for Swoop, who uses a thermal sword. He likes to be different.

And Slag and Snarl—they got a new kinetic sword and vigor sword, respectively, in Generation 2.

Energo weapons

 * Grimlock's Energo-sword.
 * Slag's Energo-sword.
 * Sludge's Energo-sword.
 * Snarl's Energo-sword.
 * Hooligan's Energo axe
 * The Quintessons have low-yield energo tendrils for close-range combat.
 * Bomb-Burst's energo-battle axe
 * Blaze Master's rotor blades can be wielded as an energo-weapon in robot mode.
 * Venom's energo-scythe.

Generation 1 cartoon continuity
Apparently, Snarl's energo-sword can fire energy blasts. He did this when the Constructicons attacked the Autobots' base in an attempt to destroy Teletraan I. Later, after going to Dinobot Island, Snarl used the energo-sword for shooting at rocks during target practice. He needs to work on his aim.