And other hidden abilities?
You get in in the Dream World.
For Gliscor, you can get DW Gligar, which is available at the Windswept Sky, which is available after you have 2,500 dream points. Evolve that Gligar for a Poison Heal Gliscor.
Apparently, Gligar is there by default.
Next time, just ask me through a comment. You don't need to ask a WHOLE new question.
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