Suggestions by @mrmovie

Nicholas G. Sims

as W. D. Gaster in VGCU: UNDERTALE

Robert Irwin

as So Sorry in VGCU: UNDERTALE

Dameon Clarke

as Mad Dummy in VGCU: UNDERTALE

Sean "JackSepticeye" McLoughlin

as Grillby in VGCU: UNDERTALE

Tommy Dorfman

as Monster Kid in VGCU: UNDERTALE

Awkwafina

as Muffet in VGCU: UNDERTALE

Melissa Fumero

as Temmie in VGCU: UNDERTALE

Pete Davidson

as Napstablook in VGCU: UNDERTALE

Justin Roiland

as Burgerpants in VGCU: UNDERTALE

Brendon Urie

as Mettaton in VGCU: UNDERTALE

Erica Luttrell

as Alphys in VGCU: UNDERTALE

Jane Lynch

as Undyne in VGCU: UNDERTALE

Jonathan Groff

as Papyrus in VGCU: UNDERTALE

Kenan Thompson

as Sans in VGCU: UNDERTALE

Steven Ogg

as Asgore in VGCU: UNDERTALE

Marisa Tomei

as Toriel in VGCU: UNDERTALE

Madison Hu

as Chara in VGCU: UNDERTALE

David Mazouz

as Asriel Dreemurr in VGCU: UNDERTALE

Toby Fox

as Flowey in VGCU: UNDERTALE

Kiawentiio

as Frisk in VGCU: UNDERTALE