Electrified Razortooth spawns only as a primary pet on the Isle of Thunder, so while roaming around, keep your eyes open. They don't spawn as often as Swamp Croaker and Elder Python; you may have to make a few rounds to find one. The good news is, Electrified Razortooth is only available in one breed, and that means less time spent farming the ideal rare.
Electrified Razortooth's abilities are mostly Elemental type, and are as follows:
Between Paralyzing Shock and Lightning Shield in the second slot, I generally go with the former. The damage triggered by Lightning Shield only works with direct damage taken, and the duration is short, at only two rounds. Paralyzing Shock is a significant amount of damage up front, and keeps the opponent in play, leaving the ability especially handy in PvP pet battles.
The Bleed effect applied by Rip comes into the equation when deciding on a third slot ability. Blood in the Water deals a massive amount of damage, but as the tooltip says, it has a high chance to miss. Good news everyone! It will always hit if the target is bleeding. And hey, if you use Rip, you're ready to go.
Another advantage of Blood in the Water is that it's strong against Elemental types. It's rare to find an Elemental battle pet that's strong against other Elementals; Pandaren Water Spirit, Thundertail Flapper, and Frigid Frostling are the only other Elemental battle pets with moves strong against their own family. Another advantage of the Rip/BitW combo is the strength of Rip against Critters. Elemental abilities are weak against Critters, so having Rip as an option is nice. Devour doesn't benefit from Rip's Bleed, but does proc a nifty heal if the opponent is killed with the ability.
Overall, Electrified Razortooth is a strong battle pet, and with a model like that? Too cute to pass up.