Hi, sorry if this has been mentioned already,
On the Gliscor checks and counters there is no mention of shell smash cloyster which, without the boost from shell smash, will 4x1hko max def gliscor with icicle spear, but, more importantly, can take a +2 eq or an unboosted flying gem boosted acrobatics and set up, that's calculated with white herb, not life orb but still..
+2 flying gem acrobatics will still 1hko and +2eq has a chance to 1hko with stealth rock dmg but I'd say cloyster still makes a viable counter to the acrobat build and with other builds, although taunt might prevent a shell smash, icicle spear can ko without boosts.
I might have missed something, but though it might be relevant...
“The price of fruitfulness is to be rich in internal opposition.”
Twilight of the Idols