Grey Gargoyle (Paul Pierre Duval)

Paul Pierre Duval, presented as a French chemist, was altered during an experiment when he spilled an unknown organic chemical compound on his right hand; the compound caused a mutagenic reaction that permanently transformed his right hand into living stone. Following the accident he adopted the alias "Grey Gargoyle" and pursued criminal aims, including quests for immortality and confrontations with superheroes. Early in his career he battled Thor, who defeated him by luring him into the Hudson River and leaving him buried at the bottom; Duval later reemerged and continued a pattern of recurring clashes with heroes and participation in villain teams.

In human guise Paul Pierre Duval is depicted as a French chemist prior to his alteration. After the accident his right hand is described as transformed into living stone. When using his power he can convert his whole body into a being of living stone, manifesting increased bulk, superhuman strength and greatly increased durability while retaining mobility. In the Fear Itself storyline, while empowered as Mokk he appears as an amplified, mythicized stone avatar capable of mass petrification.

The Grey Gargoyle's core mutation is a right hand of living stone that can transmute any matter it touches into a similar stone substance; the petrification effect on victims lasts for approximately one hour under ordinary circumstances. He can apply the same effect to himself, transforming into living stone that grants superhuman strength and durability without hindering his mobility. He uses these abilities in criminal activities and repeated confrontations with heroes (notably Thor) and has been recruited into villain teams. During the Fear Itself event he received one of the Serpent's hammers and became Mokk, the Breaker of Faith, temporarily amplifying his power to petrify entire populations (Paris was transformed to stone) before being reverted and having his victims restored by Odin. His powers have been temporarily neutralized or reversed in specific instances—contact with an enchanted weapon (the Black Knight's enchanted sword) reverted him to human form and neutralized his power briefly—and he has been contained by burial, exile to space, and other physical means in various stories.