Ok, so this is amazing, I used a kecleon with skill swap to change a tyrantitar's ability to color change, then killed it by changing its type to flying and walling it.

I copy-pasted the text here as well.
[spoiler:32lsoe0z]theonetheycallF switched in Aerodactyl (lvl 100 Aerodactyl ?).
Aerodactyl is exerting its pressure!
Pointed stones dug into Aerodactyl.
Aerodactyl lost 25% of its health.
Aerodactyl used Fly.
Aerodactyl flew up high!
Tyranitar used Ice Beam.
Tyranitar's attack missed!
The sandstorm rages.

shreyas has left the room.
Aerodactyl used Fly.
It's not very effective...
Tyranitar lost 18% of its health.
Aerodactyl lost 5% of its health.
theonetheycallF's Aerodactyl fainted.
Tyranitar became the Flying type!
Tyranitar used Ice Beam.
But there was no target!
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

theonetheycallF: FLYING TYRANTITAR!!!!!!!!!!!!
theonetheycallF: Read it and weep.
theonetheycallF switched in Registeel (lvl 100 Registeel).
Pointed stones dug into Registeel.
Registeel lost 6% of its health.
shreyas has entered the room.
shreyas has left the room.
Tyranitar used Fire Blast.
Tyranitar's attack missed!
Registeel used Iron Defense.
Registeel's defence was sharply raised.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Fire Blast.
It's super effective!
Registeel lost 37% of its health.
Registeel used Amnesia.
Registeel's special defence was sharply raised.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Fire Blast.
It's super effective!
Registeel lost 21% of its health.
Registeel used Amnesia.
Registeel's special defence was sharply raised.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Fire Blast.
It's super effective!
Registeel lost 13% of its health.
Registeel used Amnesia.
Registeel's special defence was sharply raised.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Fire Blast.
It's super effective!
Registeel lost 10% of its health.
Registeel used Rest.
Registeel fell asleep!
Registeel restored 87% of its health.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Fire Blast.
It's super effective!
Registeel lost 10% of its health.
Registeel is fast asleep!
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Fire Blast.
It's super effective!
Registeel lost 10% of its health.
Registeel is fast asleep!
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Fire Blast.
It's super effective!
Registeel lost 11% of its health.
Registeel woke up!
Registeel used Iron Defense.
Registeel's defence was sharply raised.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

theonetheycallF: Im killing you with your own ability, XD.
Tyranitar used Ice Beam.
It's not very effective...
Registeel lost 2% of its health.
Registeel used Iron Defense.
Registeel's defence was sharply raised.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Jamesb8: you are to
Tyranitar used Earthquake.
It's super effective!
Registeel lost 13% of its health.
Registeel used Rest.
Registeel fell asleep!
Registeel restored 45% of its health.
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Earthquake.
It's super effective!
Registeel lost 13% of its health.
Registeel is fast asleep!
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Earthquake.
It's super effective!
Registeel lost 13% of its health.
Registeel is fast asleep!
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 6% of its health.

Tyranitar used Earthquake.
It's super effective!
Registeel lost 13% of its health.
Registeel woke up!
Registeel used Iron Defense.
Registeel's defence won't go higher!
The sandstorm rages.
Tyranitar is buffetted by the sandstorm!
Tyranitar lost 2% of its health.
Jamesb8's Tyranitar fainted.
theonetheycallF wins![/spoiler:32lsoe0z]

It was hilarious too.

Sounds fun. You were faster than a Tyranitar? Not bad.

Quite a strategy. Sandstorm would cripple any Pokemon dealing with a Wall, but the way you dealt with him was unique lol.

This is why DD-tar is the best...except that you still would have stalled him long enough to where he couldn't kill you.

Quite unique indeed.

Hah, yeah, Tyranitar is the worst OU ever.

Speaking of Sandstorm, I have Sand Veil on my Dugtrio.

Anyways, that was one of the coolest ways to dispatch a Tyranitar ever.