Sonic the Hedgehog 3 is heavily based on the events of the 2001 Dreamcast game Sonic Adventure 2. The live-action movie doesn’t recreate the platformer’s story beat for beat, but it introduces Sonic’s revenge-driven rival Shadow, explores villain Doctor Robotnik’s family, and the moon gets blown up at one point, too. Despite keeping a lot of the same story elements, Sonic 3 does omit a few key characters like the treasure-hunting thief Rouge the Bat, and the Biolizard, Sonic Adventure 2’s final boss. However, keen-eyed fans have noticed that the movie does seem to have a blink-and-you’ll-miss-it reference to the giant reptile, and they’re feeling conflicted about it.
In the games, the Biolizard is the prototype of the Ultimate Lifeform. This is a creation by Doctor Gerald Robotnik, who went on to create Shadow as the “true” product of his research into creating an immortal being. Since Gerald doesn’t create Shadow in the movies, as he’s an alien from another planet like all the anthropomorphic animals are, there was no need to include the Biolizard in Sonic the Hedgehog 3. However, it turns out the movie does feature a brief reference to the creature during Shadow’s flashbacks. 50 years prior to the events of the movie, Shadow lived in a government facility with Maria Robotnik, Gerald’s granddaughter. The two became close like siblings, and are shown playing together while scientists attempt to perform experiments on the speedy hedgehog. One of these moments sees the pair watching a kaiju movie that, at a glance, appears to be an homage to early Godzilla films. But upon further inspection, it’s also a clever reference to the Biolizard. The giant reptile shown terrorizing civilians in the movie bears a striking resemblance to the character, from its slender mechanical eyes to the cables that extend from its jaws down its body. The movie the two watch is in black-and-white, but I imagine if it had been in color more people would have immediately caught onto this reference seeing its orange-brown skin.
On one hand, it is cool to see the movie pay homage to an important figure in Shadow’s game story, but given the way the live-action Sonic universe has previously treated one of the big monster-like enemies of the games as a comic relief prop, some fans aren’t thrilled with how Sonic 3 references the Biolizard, fearing that it’s becoming a pattern for these movies. Iblis, a fiery monster from Sonic ‘06, is referenced in the Knuckles Paramount+ show as a stage puppet in a rock opera episode. So now, having a second of the games’ big kaiju-esque monsters turned into something else has made some fans a bit wary, as they wonder if Sonic and friends will ever face something on that scale in the live-action movies.
That being said, some fans are fine with the Biolizard’s omission, saying its presence could have complicated the story, which then might not have translated to the screen as gracefully as the more focused tale did. Given the events of Sonic 3’s post-credits scene, there’s a strong possibility that Metal Overlord, Metal Sonic’s dragon-like form from Sonic Heroes, might show up in the fourth movie, so maybe we’ll get to see Sonic, Shadow, and the rest of the crew face something on that scale when Sonic 4 premieres in 2027. If not, there’s always Perfect Chaos, the final boss from Sonic Adventure, a water-based monster that floods entire cities. These movies have been playing fast and loose with the timeline, so there’s no harm in going back to a game before Sonic Adventure 2.