Also of note, the OP won the game anyway, even with spending a whole turn shooting nothing but a Wraithknight and the enemy taking two wraithknights.
This was mostly due to the fact that my opponent was playing with
(OP was incorrect - he also had a jetbike squad) troops, and as we all know, eldar troops are more or less guardsmen, and, like guardsmen, they all die in droves. I snuck a alfa-striking Plasma/Burst Cannon unit behind enemy lines, which was more-or-less the game winner.
If this doesn't demonstrate a weakness in the Wraithknight for its points, I don't know what does. Unseemly, how much damage did the WKs do, anyway? Do you *need* to kill them first thing, or can you let them lark about for a turn or two before bothering. My immediate instinct would be to not bother with them and focus on killing everything else. Now, if they're wiping a unit a turn or something, then that's a different story, but I'm not sure they can do that.
Well, it depends. The Wraithknight has a dual equivalent-of-a-railgun cannon, and that can make things messy, but what I'm more worried about is assault (It's jump infantry, and my opponent used it aggressively). Even with support fire, overwatch barely scratches the thing, and tau being tau, well... dislike CC, I'll put plainly.
The game (as far as the wraithknights were concerned) went like this:
Turn 1: there wasn't anything else to shoot at, so I shot the wraithknight, and killed it.
Turn 2: I ignored the wraithknight as my opponent's reserves all spammed out of the sky and into my backrow. The wraithknight blew up a hammerhead.
Turn 3: The wraithknight blows up a devilfish, and then my firewarriors narrowly escape CC, as the wraithknight gets 2" on its assault move.
Turn 4+5: My opponent loses all his troops, and mostly due to that I squeak a 4-1 win against eldar (but just - 2 kroot held on an objective). The wraithknight ended up on 2 wounds, having eaten through 3 tanks and 2-3 infantry/battlesuit squads (or something like that - my recall isn't too great).