"In the coming apocalypse update, there are going to be titans with a:

Originally posted by Wiz:

…front section [that] has a single Titanic-size slot that can fit weapons even stronger than XL weapons, such as the immensely powerful Perdition Beam that can fire across a whole system and potentially destroy a battleship in a single shot.

That sounds a lot like (though not 100% sure) a player obtainable version of the Titan laser that we have seen fallen empires use.

Originally posted by Stellaris Wiki:

The Titan Laser is a unique type of weapon that is only used by their namesake Titans and a handful of Guardians. Between the base damage in the thousands and the passive bonuses the enemy will have, any battleship design can be effectively one-shotted by the Titan Laser.

And we all know how much I love using Titan Lasers![i.imgur.com] Shame you can't spam these ones though..."