43.5% - 51.6%
That's how much Defensive Empoleon takes from Heatran's Earth Power, and its primarily physically defensive. After leftovers that's an incredibly low chance to 2HKO. Meanwhile the same empoleon (with these outdated EV spreads) deals 73.1% - 86.1% to Heatran off of a surf. In the off chance that a Heatran does manage to trick Empoleon, and not be a choice scarf variant, Empoleon can still take the heat.
Meanwhile, Empoleon with Thick Fat could completely wall out or counter many sets from the following pokemon:
Azelf
Celebi
Jirachi
Kingdra
Roserade
Suicune
Skarmory
Shaymin
Tentacruel
Vaporeon
Weavile
Pokemon who Surf could potentially 2HKO and outspeeds with right EV spread and assuming MAX HP EVs on the defender's part (basically I'm saying thesae guys have to go for the revenge kill)
Machamp
Hippodown
Magnezone
Please note that a good deal of these pokemon straight up counter Swampert. If I fear bulky waters and strong grass types, then I would be better to put Empoleon on my team than Swampert.
This is a Physical metagame. If this were like the other gens and were special, Swampert wouldn't have as much against Empoleon. If the metagame can switch from Physically based to specially based, than it can do the same next Gen, where Empoleon resisting Fire will be more than welcome, as will its Special Attack.
-Azelf: Isn't really seen as a sweeper anymore thanks to Scizor...and the NP set does often carry HP fighting/ground for Tyranitar and Heatran, meaning that Empoleon is not an entirely safe switch.
-Celebi: Empoleon is hit neutrally by Grass Knot/Leaf Storm/Energy Ball, while a defensive set isn't doing much back with Ice Beam.
-Jirachi: SumCM will Thunderbolt you as usual. Physical sets do sometimes have Thunderpunch...all other sets Empoleon deals with as is.
-Kingdra: Empoleon already walls Kingdra? Thick fat wouldn't help here anyway.
-Roserade: Eh, draw. Empoleon can be slept or will force Roserade out, at the cost of considerable health lost to Leaf Storm.
-Suicune: Thick fat, again, does not really help here. Offensive Suicune will CM up in your face unless you have Roar; Yawn doesn't phaze Crocune because of Sleep Talk.
-Skarmory: lol
-Shaymin: Is using Earth Power against you anyway, especially once SpD drops. Not sure what Thick Fat does for you here.
-Tentacruel: It sets up Tspikes and Spins your rocks. You do nothing. Thick fat is useless.
-Vaporeon: Happily Wishpasses...you do nothing. Thick Fat doesn't help.
-Weavile: You already 4x resist Ice...but that's irrelevant because Ice is often paired with fighting (see Low Kick/Brick Break).
Not sure where you were going with that.
As for the cat...I don't care if it's real or fake either way. The purple seems to imply poison/ghost/or dark typing if it is real, though.