They are at first glance equal as they are both pseudos and have the same base stat totals (BST).
Ability: Sand Stream
HP – 100
Atk – 164
Def – 150
SpA – 95
SpD – 120
Spe – 71
- Ok, at first glance at Tyranitar's stats, they are tank stats. Mainly for physical attacks and can survive a few hits. Sand Stream also counteracts other weather setters like Mega Charizard Y and Politoed, while at the same time buffing T-Tar's Sp. Defence. +6 points
- He has a vast move pool full of coverage moves like Earthquake and STAB Stone Edge to kill many threats. Furthermore, all of his weaknesses are covered by his coverage moves and STABs. He can also surprise the opponent with a special set although it is not recommended to go fully special. +5 points
- Combining Tyranitar's Ability, stats and movepool together, we can see that he can fulfill many different roles and has a good amount of versatility. +5 points
- Altogether he scored 16 points.
I have two move sets for him. First is the standard physical tank.
Sand Stream | Adamant / Jolly
248 HP / 252 Atk / 4 Spe
Stone Edge – Good power but not the best accuracy. Total of 150 BP with STAB.
Crunch – STAB. Decent power, useful coverage excellent accuracy. Total of 120 BP with STAB..
Iron Tail – Deals with Fairies. Good power, but unreliable accuracy.
Dragon Dance – Why does he have this and Flygon doesn't? Boosts already high Attack and middling Speed to monstrous levels.
252 attack 126 defence 126 special defence 4 HP
The second set is a surprise Special set.
Sand Stream | Calm
252 HP / 252 SpA / 4 Atk
Ancient Power – Low power, but good accuracy, STAB and a lucky chance to increase all stats. Total BP of 90 with STAB.
Dark Pulse – Useful coverage, STAB, medium power, perfect accuracy and a chance to flinch. Total BP of 120 with STAB.
Ice Beam – Excellent coverage. Medium power, small freeze chance and perfect accuracy.
Earthquake – Surprise attack and Tyranitar's only physical attack.
Now for Garchomp!
Ability: Sand Force
HP – 108
Atk – 170
Def – 115
SpA – 120
SpD – 95
Spe – 92
- Wow! That's a monster attack paired with a monster ability and decent bulk. Mega Garchomp is built for sweeping and semi-tanking, plus his special/mixed set is more usable than Tyranitar's. +7 points
- His movepool doesn't suit the special surprise set but my Lord it suits a physical one. With that great coverage, so many stratagys can be used. +6 points
- Combining Sand Force, his stellar Attack and STAB Earthquake, he is a monster. +7 points
- Altogether he scored 20 points.
I want to put so many sets but I will only put two.
Sand Force | Adamant
252 Atk / 252 Spe / 4 HP
Earthquake – Awesome power and accuracy and is just godly when you factor in Sand Force and STAB. Total BP of 150, not including Sand Force.
Sandstorm – Lets you nab the Sand Force boost.
Dragon Claw – STAB and good accuracy. Total BP of 120.
Crunch – Medium power, useful coverage and good accuracy.
Next is a trick set. [EDITOR'S NOTE: The following set is banned on Smogon, but for WiFi/in-game it is fine.]
Sand Force | Impish
252 HP / 252 Def / 4 Atk
Sandstorm – Used to set up Sand Force.
Swagger – Omg so annoying!
Sand Attack – Nothing better than lowering accuracy.
Earthquake – It's just godly.
Overall, Mega Garchomp wins by 4 points, but both are good in there own respects.
It's all up to you and your opinion.
As for which one for your team, I would suggest Mega Garchom because most of your teammates are already tanky and you need some heavy offense.