Weak against Dimeritium Bomb, Elementa, Quen.
Gargoyles are stone statues brought to life by magic in order to guard mages' laboratories and lairs from intruders. Their appearance alone has scared off more than one prospective burglar. Those who do not take fright at the sight of these horned and winged monstrosities usually die shortly thereafter, torn to shreds by stony claws.
Gargoyles can attack quickly, despite their heavy forms. They mostly make use of a projectile attack that sees them lobbing a clod of earth your way, but it's easy enough to avoid if you're paying attention. At close range, the chubby monsters will swing their arms at you, but again, dodging the blows is fairly simple as long as you don't overstay your welcome while you're hacking into their stony forms.
A gargoyle's best weapon is arguably its stomp. This attack sees the statue-like creature smash one foot on the ground, which creates a damaging 360 degree shockwave that'll break straight through your guard and leave you stunned. With that in mind, always try and have quen cast so that you can absorb the blow.
Similarly, quen is a good idea for when you're fighting a gargoyle out in the open, too. With no ceiling above its head, a gargoyle can leap into the air and smash down somewhere near within the blink of an eye. The resulting shockwave can deal damage, and leave you wide open.