lascannon firepower

Steel Tread was bulkier than Oathkeeper had been, with thicker armour and more firepower. Sponson-mounted heavy bolters offered anti-infantry point-defence. A tank-busting lascannon jutted from the vehicle's prow, while a pintle-mounted storm bolter on its turret sat above the Russ' main weapon.
...
A lascannon beam punched through the turret of a mutated Leman Russ, killing its main gun in a belch of smoke.
...
The dust was still clearing as the lascannon beam strobed through it, sparkling with particulates, stabbing into the flank of the enemy Punisher. The tank deformed from within as its power plant went up. Its top hatch rocketed skywards. Flames belched from its ruptured hull.
...
A gruesome vehicular mass rolled forward, two tanks fused together by flesh and bone. Its twin turrets focused their fire on Ogre, hitting the Demolisher with a pair of battle cannon shells at point-blank range. One of the Demolisher's sponsons was reduced to sparking scrap and a terrible gouge was torn in its prow armour.

Jorgens slowed his tank even as the enemy vehicles sought to encircle him and fire on the lighter armour to the Demolisher's rear. Ogre swerved then stopped hard, punching into reverse and traversing its turret. The Demolisher cannon fired at the same time as the prow-mounted lascannon. One blew apart a renegade tank crawling with eyes. The other punched through one of the conjoined traitor tanks and set it ablaze.
...
Ogre’s main gun spoke, and a Leering Skulls tank detonated. Another backed frantically out of the Demolisher’s path, ichor welling from its cratered hull as its turret swung to bear. Ogre’s lascannon spat a beam of searing light and the enemy tank burst like a ruptured organ.

Steel Dread