Bowser's Dank Rave 3 introduces Toadette as a significant character in the fictional Nintendo 64 game series. The 'MLG Expansion' suggests a significant addition, perhaps offering new levels, characters or gameplay mechanics inspired by the online gaming community and the 'MLG' (Major League Gaming) culture. The original Bowser's Dank Rave 3 presumably laid the foundation for the game's world and gameplay, likely utilizing the unique blend of action, adventure and rave-themed settings established in earlier installments.  As with the other games in the series, there is no real developer or publisher for this fictional game.

Bowser's Dank Rave 3 - Toadette's MLG Expansion

Bowser's Dank Rave 2 - Return of the Illuminati Dubstep Party