1. Guest; 450$ (Rarity: Epic)

2. SNACKCORE; 600$ (Rarity: Legendary + replaces CHEEZBURGER with chips bag)

3. Hotdog; 650$ (Rarity: Legendary + custom voicelines/SFX, replaces CHEEZBURGER with hotdog)

4. Shedletsky; 700$ (Rarity: Ancient + custom voicelines, replaces CHEEZBURGER with fried chicken)

5. Genesis; 800$ (Rarity: Ancient + custom animations, custom SFX)

Guest was the classic avatar for the special Guest function originated in ROBLOX available from 2008 to 2014 before getting removed from the platform.

SNACKCORE refers to a appearance of a main protagonist of GASA4 (Get A Snack At 4AM) who's main goal (and the most basic ending) is eating a chips bag and go to sleep.

Hotdog is a playable survivor from the deck in Die of Death, but in Termination404, he can't be fat.

Shedletsky refers to, as you guess, a former admin of ROBLOX, John Shedletsky.

Genesis was the experimental avatar of the Dynablocks before getting revamped into ROBLOX.