Sonic Party 3 is the third installment of the Sonic Party series, and the last one for the Nintendo 64. The game is centered around the Millennium Star, who replaces Omochao as the host. The most notable change is that players can now hold up to three items instead of just one. The game includes 70 new minigames, as well as a feature unique to the Sonic Party series: duel boards, on which two players fight each other using partners. The game is also the first game in the Sonic Party series to have a solo mode story campaign.
As in all Sonic Party games, there are always other modes to play:
- Mini-game Mode: Players can play all the mini-games that they have collected here, even secret mini-games.
- Story Mode: A single player can go through the storyline. It is set what boards have to be completed in what order. There are Battle Royale and Duel boards. After each Battle Royale board, the player has to fight a certain character on a duel board for a Star Stamp. If the player is to duel with the character they are playing as, they will battle Tails instead. Unlike Party Mode and Mini-game Mode, Rouge and Shadow are unplayable in this mode, instead acting as NPC's.
- Party Mode: A multiplayer that can go through Battle Royale, Duel Mode, and can also go through settings.
The game brings back the original six playable characters from the last two Sonic Party games and introduces two new characters, Rouge the Bat and Shadow the Hedgehog. However, they can only be playable in Party Mode and Mini-game mode.
- Sonic the Hedgehog
- Miles "Tails" Prower
- Knuckles the Echidna
- Princess Sally Acorn
- Cream the Rabbit
- Amy Rose
- Shadow the Hedgehog
- Rouge the Bat
- Ryan Drummond as Sonic the Hedgehog and Metal Sonic
- Corey Bringas as Miles "Tails" Prower
- Michael McGaharn as Knuckles the Echidna
- Lacey Chabert as Princess Sally Acorn
- Sarah Wulfeck as Cream the Rabbit
- Jennifer Douillard as Amy Rose
- David Humphrey as Shadow the Hedgehog
- Lani Minella as Omochao and Rouge the Bat
- Deem Bristow as Doctor Eggman