Bumbo 'Olaf' Frostonai is a snowman-like Bumbo created by Iskall85 in Season 5.
Bumbo Frostonai was created during Iskall85's Christmas 2017 livestream, and doesn't appear in the series until after already being built.[1]
Frostonai is somewhat unique in the spelling of his name, ending in "-onai" instead of "-oni," as seen with the sign Iskall85 placed inside him.