There's really no point in using Dragon Dance normal Tyranitar, since it's just too slow at +1 to outspeed anything. If you're gonna use DD, I would suggest this moveset:
Tyranitar-Mega @ Tyranitarite --- The small speed boost that Tyranitar gets from mega evolving really helps with attempting to sweep
Ability: Sand Stream
EVs: 252 Atk / 4 SpD / 252 Spe
- Stone Edge --- Quite frankly just the strongest move Tyranitar can use, so it should be used as the primary attack when trying to sweep. Rock Slide can be used if you're afraid of missing, but Stone Edge's extra power is usually worth the risk.
- Crunch --- Crunch is the strongest dark-type move Tyranitar has access to (Other than Payback and Foul Play, but both of those attacks are completely pointless to run on a Dragon Dance boosting set), so it should be used on all Dragon Dance variations.
- Ice Punch/Fire Punch/ Thunder Punch --- After dual STAB, you should use one of the elemental punches to knock out Pokemon like Scizor, Landorus and Gyarados at +1. Iron Head or Poison Jab are also usable If you're really scared of fairies like Clefable or Diancie.
- Dragon Dance --- Dragon Dance is one of the scariest boosting moves in all of Pokemon, since it raises your attack to break through very defensive Pokemon, and it also raises your speed to outpace everything in the metagame at +3. Rock Polish is a possible replacement for Dragon Dance, in order to outspeed almost everything in one boost, but since DD also raises your attack, it is almost always preferred.
If you want to use a Defensive Tyranitar set, this is what I suggest:
Tyranitar @ Smooth Rock/Leftovers
Ability: Sand Stream --- You might think of using Unnerve if your team doesn't have any Pokemon to take advantage of the sand, but Sand Stream is always the better ability on Tyranitar. It breaks opposing Focus Sashes on switch-in, and boosts Tyranitar's already relatively high Special Defense even further.
EVs: 252 HP / 156 Atk / 100 SpD
- Ice Beam --- Looking at this set you might be thinking that using a special move on a Pokemon with such a high attack stat would be completely pointless, but Ice Beam is very useful on this version of Tyranitar. It hits Landorus and Garchomp VERY hard because they run physical defensive sets, and since they don't have any recovery moves, they cant stay in on you, meaning you can either Pursuit them, or use Stealth Rock.
- Stone Edge --- The strongest attack that Tyranitar has access to, when accounting for STAB, so it should always be used on all versions of Tyranitar. It knocks out Volcarona in one hit, and since your Special Defense stat is so high from Sand Stream, it can be used to stop a Volcarona sweep.
- Pursuit --- Traps a lot of Psychic-type Pokemon like Latios, Latias, and Alakazam (If they switch, Latios and Alakazam always get OHKO'd after Stealth Rock damage, and Latias gets OHKO'd after Stealth Rock and one turn of Life Orb damage). This can be switched out for Crunch if you'd rather just have an attack that will always be strong.
- Stealth Rock --- Since it's so bulky, Tyranitar will have a lot of opportunities to set up Rocks for your team.