Sonic 3 & Knuckles (with voices!) Episode 18: Knuckles Adventure part 6

Having survived the pain of the Sandopolis Zone, Knuckles has jumped from the frying pan and into the fire as he enters the Lava Reef Zone. After making his way through the heavily trap-filled volcano, Knuckles finally reaches the Hidden Palace only to discover that the Master Emerald is missing. Warping to what remains of the Sky Sanctuary, our hero finally learns the truth of the situation, Mecha Sonic is still alive! The evil robot doppelganger is the one behind the resurgence of Badniks, and seeks to use the emerald's power to get his revenge on Sonic. Only Knuckles the Echidna stands in the way of Mecha Sonic and his goals...

Featuring the official voice talents of:
Scott Dreier - Knuckles the Echidna
Ryan Drummond - Mecha Sonic / Sonic the Hedgehog