Final bosses don't come much more creative or unhinged than Photoshop Flowey (aka Omega Flowey) at the end of Undertale's neutral route. This heavily segmented battle reveals Flowey's final form ...

Omega then walked out to the ring in full Sans gear, complete with a skull mask. Matt and Nick Jackson, The Young Bucks, soon followed in the same Street Fighter gear they used for a six-man tag ...

Omega's standard entrance video was interrupted with a dialogue scene in the style of Undertale - with custom graphics and authentic talking noises - where Sans offers to tag in.

This is no better felt than in the climactic battle with Photoshop Flowey (aka "Omega Flowey"), the final boss for players who opted to take the netural route through the game.