Electric bolts of high current render circuitry burned beyond repair (afaik). Currently, in Tremulous, the zaps simply damage the structures and barely anyone uses it since it's kind of ineffective, unless he wants to annoy the ckits. If a mara starts damaging turrets with zaps, the turret will keep on shooting the attacking mara or anyone for that matter.
Now what I suggest is something that can somewhat/significantly improve the mindset of a teamplay and a coordination of various aliens attacking a base together, while not being too OP.
The zaps will deactivate the damaged turrets for as long as he keeps zapping. Not burn their circuitry, but rather thanks to some protective measures from humans it would merely disable it for as long as zaps are zapping. Perhaps humans could get some late Stage 3 upgrades on the defense computer that would reinforce the circuits of human buildings so the circuitry would be completely isolated.
Now such a zapping attack could turn into an infinite loop of zapping until their base is overrun and this would be quite OP. But, for this case, there should be a limit of zapping introduced, since the Mara/Narba isn't a damn perpetuum mobile that harnesses dark energy from his vicinity. Something like an organ that works as a storage inside the Narbatucker, like an organic capacitor that has to regenerate its electricity stored inside after some use. Same would go for the EVERGASING ADVANCED BASIFUCKINGLISK IN ATCS RIGHT UNDER THE FUCKING HUMAN BASE AT HUMAN STAGE 1 GETTING ENTIRE HUMAN BASE HIGH.
Sounds cool?