Wave Serpent
The Wave Serpent is the Eldar's dedicated troop transport, an anti-grav skimmer that flies through the battlefield, blasting away with a twin linked turret weapon while rushing to get your troops right into the heart of the army.
Like all Eldar vehicles there is not much difference between it and say the Falcon or the Fire Prism besides some variation in weapons. This is basically the Eldar are shameless corner cutters who won't fix what ain't broken. That Or Games Workshop can't be bothered to produce multiple different molds and uses the same one as the staple Eldar one.
On The Tabletop
The 7th Edition Eldar Craftworlds Codex moderately toned down the Wave Serpent. They still are strong bastions of firepower, but their abilities are less OP as fuck as they are decently strong.
- How much firepower? Still has the classsic Twin-linked Shuriken Catapult, shuriken cannon, but the Scatter laser no longer gives Laser-lock, and the Serpent Shield's rape-tastic shooting is now a once per game S6 Ignores Cover, Heavy 2D6. Result? Now have slightly less dakka than before, but are still spammable and can put out quite a few shots if you get lucky with the Serpent Shield.
- How hard are they to kill? With front and side AV12, fairly moderate AV Skimmer with the ability to jink and the infamous Serpent Shield intact. But, now if you dissipate the shield to shoot it once per game, you lose the benefits. In short, quite hardy unless you force them to shoot the shield/hit them with Ignores Cover weaponry. In addition, per the latest ITC FAQ, the Serpent shield is indeed a weapon, that can be removed by Weapon Destroyed. Sure it's unlikely, given the damn thing can negate weapon destroyed on a 2+, but I fucking dare you to roll a 1.
- How spammable are they? To make up for the lack of laserlock and the new Serpent Shield, it's now slightly cheaper and can still be taken by anything on foot. Still facing 3-6 of them in a list.