Defensive latias with reflect / roost.

X-scissor

Well, I was assuming it's sashed.

If not then defensive skarmory, then whirlwind it out.

sashed / banded*

wut
Skarmory is like 2HKO'd by banded close combats i think

I've had a skarmory survive a CC from a lucario with 67%. Well enough to lay spikes while he switched out.

Well this is a Terrakion

well shit.

I never face terrakion, simply because i can see it coming. If i know they're switching to it, I send out haxorous and outrage him down.

Terrakions outspeed em though

I use choice scarf for speed boost purely for situations such as that.

Ludicolo

ohoho

Swift swim
Or you could go for focus sashed Toxicroak

Swift swim is illegal with drizzle
and i guess so, but terrakion also gets quick attack

2 Hit KO, you could just rain dance

Well, this is max hp and defense
its a one hit kill without the EVs
With these EVs i dont think ludicolo will one hit

Toxicroak, focus sash, drain punch.
Then go for a sucker punch if you can.

Anything faster than it that can learn a Water, Grass, Fighting, Steel, Psychic, or Ground move

As are most things that can learn said type moves