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Title says it all. I think they would be extremely simple to implement, with the legs from the knights being pretty much interchangeable.
I think it would be ok in nearly any setting, after all you are still using GW models. Also a Space Wolf on a horse posing as TWC would't get confused with any other entries from our codex, so no problem on that front either.
"I am the architect of fate!"
Though there are MUCH better models out there to use. Like Vampire Counts Dire Wolves or non-GW wolves. A marine being converted to mount a wolf should easily meet the 50% requirement for tournaments.
Notable Achievements: Farseer w/ SS taking down a Monolith all by itself in one shooting phase. A Warlock w/ SS in a Guardian squad on an objective taking down a Soul Grinder in one Shooting phase. 2nd turn 2 DSing Trygon Primes going from 6-0 wounds during turn 3.
The new Daemons release bloodcrushers comes 3 to a box in plastic, and is going to make an excellent "counts as" thunderwolf cavalry in my chaos army. My local store is going to see Canis Daemonborne soon.
The Emperor died ten thousand years ago.
I couldn't resist, and got a box of boar boyz. Instead of Orks, I'm using Marine Models and a little greenstuff to make my 'Thunder-boar' cavalry. ^_^
"Any job worth doing, is worth doing with a powerklaw."
I used my blood crushers and they worked get especially since I use 13th company space wolves... now think of something else and not use my idea! Lol jk