Eight

Eight was a character in Numberblocks Basics.

He never appeared in any games ever again apart from remasters of the first game.

Classic Eight (NB)
Classic Eight debuts in Numberblocks Basics.

In-game, he appears on top of the screen and will start approaching you. To get rid of him, press the Shock button. If you don't do it in time, he will jumpscare you.

Appearance
Eight is magenta with 8 blocks in a 2x4 rectangle. He has 2 eyes with dark magenta-coloured goggles with 4 eyelashes on each side, totalling up to 8. He also has 8 dark magenta tentacles for limbs, like he's an octopus, hence his super-hero alter egos "Octoblock" and "Octonaughty".

Trivia

 * Eight's jumpscare sounds like the infamous "Boris the Teeth Guy" from various GoAnimate videos.
 * Eight can get easily offended by Two.