I wouldn’t advise using two attacks just because Reflect Type is necessary to find set-up opportunities and Substitute is fantastic with status spreading and to find free turns, but Surf is at least viable to make sure you have something in worst case scenario type situations against Dark types and perhaps Heatran that lack Toxic that you want to kill without giving the opponent too many free switch turns on CM, but even that’s a pretty specific middleground type situation that generally doesn’t merit dropping the support move for the second attack.Thanks. So iff you're not running toxic spikes, are t-bold or surf better options than sub/reflect type? And how can Latias ever outlast Tyranitar, even if the latter is poisoned?
If Tyranitar is Poisoned and Stealth Rock (or Spikes, for that matter) are up, it’s very easy to outlast Tyranitar. Consider that CB Tyranitar is compressed a ton as it lacks longevity and it is often relied on as a breaker and trapper — if you have it status’d or crippled/weakened already and you avoid a Pursuit trap or two via Substitute scout or timely Reflect Types, then it is basically dead in that scenario. Wish Clefable support for Tyranitar is often welcome for this reason, but that’s a whole other story for another post.