Tyriok Gadsworth

is a cartographer who Vox Machina met while he was an amateur. As an NPC, he is played by Matthew Mercer.

Appearance
As of early 811 PD, Tyriok was a young, thin, human male, with short brown hair and spectacles. Due to an attack by basilisks and a hasty de-petrification, his right arm is missing below the elbow.

Personality
When Vox Machina met Tyriok in a tavern, he was reasonably helpful (offering advice and parchment, though not the map he was working on or his compass) and suggested that they avoid some hazardous terrain and places where dangerous creatures tend to live. He was slightly creeped out when Grog asked who his girlfriend is.

When he was guiding Vox Machina in the Frostweald, he was uncomfortable with the idea of carrying a weapon.

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

and
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 where 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.

Tyriok helped guide the party in the Frostweald. He wasn't keen on the idea of carrying a powerful magic weapon, and rejected one dagger that Grog said would make him infertile. During a fight with some orcs, Tyriok remained hidden. When Tyriok and Vox Machina parted, they suggested he go to Whitestone for safety, and he agreed. He kept his satchel, just in case his petrified research could be recovered later.

Critical Role: Tal'Dorei Campaign Setting
In the Campaign Setting sourcebook, set in 812 PD, is a map of the continent that says it was "[t]aken from actual surveys conducted on travels by Tyriok Gadsworth, Chief Cartographer to the Guild of Beacons", indicating that Tyriok was no longer an amateur.

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.)
 * Tyriok is ambidextrous (or he was).
 * Liam O'Brien was dressed as Tyriok during, which aired the week before Halloween 2016.