Ttar doesn't really need support is my point
Well, saying that a support 'mon doesn't need support is both generally true and not very meaningful - Miltank doesn't require support either.
What you're actually getting at here is splashability, and Ttar('s usual, Pursuit set) is not especially splashable - you don't really want to use it unless you have something on your team that needs Pursuit support (usually MonoLax or a spinner). If you don't need that Pursuit you probably want a different FireLax answer, either one that gives different support (i.e. Miltank providing Bell, Gengar/Missy providing spinblock) or one that has more offensive presence (i.e. Rhydon with STAB Earthquake, or again Gengar via Exploding on Raikou).
Mixed Ttar is really not that impressive unless it runs AncientPower and actually gets the boosts. It doesn't have access to sleep, instant recovery or Explosion, it's susceptible to all forms of status and residual, and its STABs are nothing special due to awful base power. All it's really got going for it is its statline (which is admittedly good).