Undertale

Undertale is a role-playing game developed independently by Toby Fox with additional art by Temmie Chang in the Game Maker: Studio engine. It was released for Microsoft Windows and Mac OS X on September 15, 2015, and for Linux on July 17, 2016. The game has been met with overwhelmingly positive reviews.

Summary
See Undertale Wiki for info.

Sound Effects Used

 * Sound Ideas, CARTOON, LAUGHTER - HIGH PITCHED CRAZY LAUGHTER 01 (This sound is used in normal and low pitches as Flowey's laugh, but has been slightly edited to sound more demonic.)
 * Sans Talk

Audio Samples
The edited versions of Sound Ideas, CARTOON, LAUGHTER - HIGH PITCHED CRAZY LAUGHTER 01: