Tyriok Gadsworth

is an apprentice cartographer, whom Vox Machina met in. As an NPC, he is played by Matthew Mercer.

Tyriok first met Vox Machina in Vasselheim, where they stopped in a tavern to ask for directions on their way to the Fire Ashari. He advised them to stay on the road for safety, and also requested that they take note of any landmarks or other information he could use for his maps.

Tyriok met the party a second time when they were traveling through the Frostweald to find Kamaljiori. He had been traveling all over Tal'Dorei with two companions when they were attacked by basilisks and turned to stone.

Fortunately, Vox Machina passed near the place were Tyriok had been attacked. The party defeated the basilisks and revived Tyriok with a Greater Restoration spell. However, his hand had been broken off while he was petrified and they neglected to reattach it first, so he ended up losing his hand for good. All of his research was also lost, as it remained petrified along with his broken-off hand.

Trivia

 * Tyriok is the third character featured in Critical Role missing a hand, preceded by Anna Ripley and Cerkonos, and followed by Shale.  (Victor is missing his fingers on his right hand, but he still has the actual hand.)
 * Liam O'Brien was dressed as Tyriok during, which aired the week before Halloween 2016.