Thermal lance

A thermal lance is a melee weapon that fires blasts of searing heat from its tip.

Fiction

2019 IDW continuity

After being ordered by Chromia to raid Security Operations' armory for weapons to take on The Rise, Sideswipe eagerly singled out the thermal lance. While Windblade was uncertain a thermal lance was what the weapon actually WAS, Sideswipe remained adamant about it. He soon got to test it out against Flamewar, who readily identified it, then proceeded to completely overpower Sideswipe's lance with her own built-in flamethrowers. The Cracks Beneath Your Feet Part Three

Sideswipe held onto the thermal lance and brought it with him for another operation under Prowl's command to raid Swindle's. He beat down Storm Cloud with the lance without even having to fire it. Swindle's After the Decepticons invaded Crystal City and Strika's Heavies broke through Autobot defenses, Sideswipe used his thermal lance to cover his comrades' retreat. A Dust of Crystals

Alternate future

In a possible future where Exarchon had conquered Cybertron, Powerglide wielded a thermal lance. When Powerglide was killed fighting Exarchon's forces, Bumblebee took up the lance to buy Jumpstream enough time to teleport away. Test Flight II