Tiso

Tiso is an adventurer who seeks the Colosseum of Fools for the sake of challenge. He presumably fights using his shield, which he claims conceals a "deadly surprise."

He is arrogant, thinking of himself as the ultimate warrior and showing nothing but contempt for the weak. He almost pays no notice to The Knight until later on, and even then he finds them beneath him.

Despite his bravado, the player never actually fights him, as he dies off-screen in the Colosseum of Fools, his body later found dumped by the acid pits at the bottom of Kingdom's Edge with the other slain warriors.

First Encounter, Dirtmouth
Tiso can be found next to the well in Dirtmouth. He lightly hints at the Colosseum of Fools and expresses his urge to challenge the Knight.

Second Encounter, Forgotten Crossroads Stag Station
Tiso can be found sitting on the Bench in the Forgotten Crossroads Stag Station, where he expresses his dislike for the Stag Stations' convenience and that a real warrior travels without help.

Third Encounter, Blue Lake
Tiso is seen standing at the eastern shore of the Blue Lake, gazing over the water and expressing his dislike for peace and serenity.

Fourth Encounter, Colosseum of Fools
Tiso is found sitting on the bench below the Colosseum of Fools, looking at the ground as if waiting.

Final Encounter, Kingdom's Edge
Tiso's corpse is found lying on a ledge in Kingdom's Edge.

Bonus Encounter, Godhome
Tiso makes a joke appearance with a fake out boss sequence in the Pantheon of Hallownest before being subsequently crushed by Brooding Mawlek.
 * If Tiso's body is dream-nailed, it will say: "...Why?...", the same as his real world corpse.

Trivia

 * Tiso is named after Tiso Spencer, the Kickstarter backer who designed him.
 * There is coincidentally a Brooding Mawlek in the Trial of the Fool. Tiso also disappears and his corpse can be found after this Trial is available. This combined with his comedic death in Godhome could imply that the Mawlek is what killed him during the real-life Trial.

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