Metal Construct. As a metal construct the Dwemer Spider does not need to breathe, however it is incapable of swimming.   Spider Climb. The Dwemer Spider can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.   Explode on Death. The Dwarven Spider explodes in sphere of lightning bolts upon its death, any creature within 10 feet of the Dwarven Spider when it dies must make a Dexterity saving throw, taking 2d8 lightning damge or half as much on a successful save.