Cybershark is a Maximal from the Beast Wars era.
Cybershark is a skilled tracker and expert in undersea combat. Though not particularly bright in a general sense he can be quite calculating when it comes to tracking down his prey, and is a fearless fighter. He honed his skills as a Bounty Hunter tracking down a rogue group of Cybertronian Space Pirates. Though dedicated to the Maximal cause, Cybershark is not a team player, ironicly this often puts him at odds with his commander, the likewise independent Depth Charge.
(It seems likely that the Beast Machines Maximal Hammerstrike (BM) may be a third form of Cybershark, as he becomes a hammerhead shark, has the same duel functions, and indeed cribs pretty much his entire bio note from Cybershark's previous one.)
Fiction
IDW Beast Wars Comics
Cybershark was one of the protoforms left behind by the crew of the Axalon on prehistoric Earth. He was activated and put in chronal phase by Razorbeast at Magmatron's request, but was protected from Magmatron's Predacon shell-program by a viral code Razorbeast inserted. Coming online in his original (non-TM2) form in the middle of the ocean, he was one of the first Maximals to hear Razorbeast's signal.
He is later seen swiming through a narrow strait with fellow sea-bound Maximal Claw Jaw (BW).
Toys
Cybershark began the Beast Wars transforming into a hammerhead shark. When a tregger was pushed the top "hammer" part of the head would fire like a missile. When he was transformed into a Transmetal 2 his meched-out shark mode became more like a classic great white and he gained a flight mode.