These codes can either be entered at the naming screen (where you input your name and nickname) as the nickname, or later on at the "secret icons 2" screen when selecting a buddy icon.

Code	Effect
Jacksepticeye	Unlocks the Jacsepticeye logo as a buddy icon.
Markiplier	Unlocks the Markiplier logo as a buddy icon.
Pewdiepie	Unlocks the Pewdiepie logo as a buddy icon.
aquateen	Unlocks an Aqua Teen Hunger Force buddy icon.
chilledchaos	Unlocks the Chilled Chaos logo as a buddy icon.
freddy	Unlocks a Five Nights at Freddy's buddy icon.
minecraft	Unlocks a Minecraft buddy icon.
morty	Unlocks a Rick & Morty buddy icon.
newgrounds	Unlocks a Newgrounds buddy icon.
overwatch	Unlocks an Overwatch buddy icon.
southpark	Unlocks a South Park buddy icon.
undertale	Unlocks an Undertale buddy icon.
va11halla	Unlocks a VA-11 HALL-A: Cyberpunk Bartender Action buddy icon.