Sonic the Hedgehog 3 ending explained: What does that post-credits scene mean?

Meanwhile, Keanu Reeves joins the cast as the voice of iconic video game antagonist Shadow the Hedgehog, whose presence gives Sonic perhaps his biggest threat yet.

The film is another fast-paced adventure that seems all but certain to delight kids, as Sonic teams up with his old pals Knuckles and Tails for another vital mission, and it ends in pretty explosive circumstances.

With a report from Variety indicating that a fourth Sonic film is already in the works, there's also a major post-credits tease that gives a good idea of what might be happening in the next film, including more new characters to be introduced from the games.

Read on for full spoilers for Sonic the Hedgehog 3, including the ending and post-credits scenes explained.

Sonic 3 ending explained: Full spoilers for threequel

Towards the start of the film it appears that Dr Robotnik has switched sides to work alongside Sonic in the face of a bigger threat from Shadow. But alas, that alliance doesn't last all that long – and when he discovers his grandfather is still alive he begins working alongside him, with the pair hatching a plan to take over the world using the Eclipse Canon.

They task Shadow with breaking into G.U.N. headquarters to collect the key that they'll need for this weapon to work, with the hedgehog only too happy to assist in the belief that he is avenging the death of his old friend and Gerald's granddaughter Maria.

Despite resistance from Sonic and his allies, Shadow is successful – and indeed Tom (James Marsden) is badly injured in the struggle, which upsets and angers Sonic. Spurred on, he realises that he can only hope to defeat his adversary by unleashing the Master Emerald – and goes ahead with this plan despite the warnings of Knuckles.

And so Sonic goes full Super Sonic and heads up to the Eclipse Canon, where Ivo and Gerald have had a falling out over the fact that the latter wants to destroy the world, rather than simply rule over it. A fight between the family members then ensues while Sonic and Shadow simultaneously fight their own battle.

In the latter battle, our hero eventually forces the upper hand but decides to forgive Shadow, and manages to talk him down from his extreme position and desire to destroy the world. The pair then join forces to stop Gerald from doing exactly that, uniting to intercept the Canon's beam as it fires towards Earth, with Knuckles and Tails also trying to divert its path and stop it from colliding with the planet.

But they can only do so much, and the real power now rests with Ivo. After finally beating his grandfather in their duel, the erstwhile villain realises that his only course of action to truly divert the beam away is doing so manually, which would require sacrificing himself inside the now over-heating canon.

He does just that, and the day is saved, with the beam missing Earth (although it does shave off a portion of the moon!). Meanwhile, Shadow also appears to sacrifice himself to move the canon further away from Earth as it explodes and preventing further collateral damage. They weren't so villainous after all, then!

Sonic 3 post-credits scene explained: Who is Amy?

The first post-credits scene picks up after Sonic sped away during a race with Knuckles and Tails that occurred at the very end of the movie.

He wins the race by such a huge margin that he soon finds himself alone in the woods in what appears to be a very dangerous situation, as he's surrounded by an army of robot Sonics and looks helpless to their attack.

But thankfully, out of nowhere, someone comes to his rescue: a pink, hammer-wielding hedgehog. Fans of the games will know this is Amy Rose, a popular character who also happens to be Sonic's girlfriend, so this will definitely make things interesting when she inevitably becomes a major character in the next film.

We can't wait to find out who will voice her – and given we've already seen such starry names as Idris Elba and Keanu Reeves joining the voice cast, we feel pretty certain that it could be someone very well known!

Sonic 3 end-credits scene: Is Shadow alive?

Above, we noted that Shadow appeared to sacrifice himself in moving the exploding Eclipse Canon further from Earth, but the final credits scene teases that wasn't the case after all.

In the scene, we see him returning to Earth almost instantly, so it looks like we can expect to see more of Keanu Reeves voicing him next time out!

Sonic the Hedgehog 3 is now showing in UK cinemas.

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