The Kao is an obstacle that appears in the Sonic the Hedgehog series. They are gigantic stone wheels that roll around, either chasing after the player or obstructing their path.


Heroes Kao

A Kao seen from the front.

The Kaos are incredibly large circular while rocks. They have spikes protruding from their sides and vicious red faces painted on their surface that show curved eyes and sharp teeth.

In gameplay, they roll around their level, their purpose being to roll over the playable characters and flatten them. When making contact with a Kao, instead of being crushed by it, the playable character will take damage. In addition, due to their huge weight and size, the Kaos can break anything smaller in their path.

Game appearances

Sonic Heroes

Kao chasing Team Sonic

A Kao chasing Team Sonic in Ocean Palace in Sonic Heroes.

The Kaos made their first appearance in Sonic Heroes. In this game, they appear in Team Sonic and Team Dark's version of Ocean Palace. In gameplay, Kaos can roll fast enough to keep up with the playable characters. In addition, they appear to be semi-controlled: when they collide with a character, they stop and retreat a bit, and when following a playable character they adjust their speed according to the playable characters' rather than moving at constant speed. Touching a Kao in gameplay will result in the playable characters taking damage.

In Ocean Palace, the Kaos appear after the playable characters are send flying towards the last stretch of the stage. When they are first encountered, a single Kao will come rolling up from behind the playable characters and chase after them. Halfway through this Kao escape section, another Kao will join the first one. Later, a third one will join the chase. Ultimately, the player will have three Kaos chasing after them until they reach the end of this section. There, the player will hit a Jump Panel that will send the playable characters flying across the sea and towards the Goal Ring while the Kaos fall into the sea.

Sonic Generations


A Kao in Seaside Hill Act 1 in Sonic Generations.

In the console/PC version of Sonic Generations, the Kaos appear in Seaside Hill Act 1 and 2, with each Act having a different version of the Kaos. The Kaos in Act 2 are identical to the Kaos that appeared in Sonic Heroes, except that these ones have refreshed textures. The Kaos in Act 1 on the other hand look similar to those in Act 2, except they have smaller spikes on their sides.

In Seaside Hill Act 1, a Kao will come rolling towards Classic Sonic when the player nears the end of the Act. From there, the Kao will pursue Classic Sonic until he reaches the end of the Act. Much like in Sonic Heroes, the Kaos here adjust their speed in accordance to how fast Classic Sonic is going. If Classic Sonic touches the Kao, he will take damage. In addition, the Kao will roll over Classic Sonic if it can. After a while however, a new Kao will come rolling in from behind to pick up the chase after Classic Sonic; in essence, this means the player cannot avoid the Kaos' pursuit. Additionally, the Kaos can move through shuttle loops. Eventually though, the Kaos will fall into the sea, just as the player gets near the Goal Plate. In Seaside Hill Act 2 on the other hand, several Kaos appear all at once. However, they will not chase Modern Sonic. Instead, they roll across road that the player needs to follow, creating obstructions that the player must avoid. Touching them will cause Modern Sonic to take damage. Towards the end of the Act in particular is a tunnel inside a temple with a series of Kaos that roll back and forth across road.

Sonic & All-Stars Racing Transformed

In Sonic & All-Stars Racing Transformed, the Kaos are featured along a single road segment of the Ocean View race track. Like in Seaside Hill Act 2 in Sonic Generations, the Kaos can be found rolling across the road, causing damage to any racer who makes contact with them and making them spin out temporarily.

Team Sonic Racing

In Team Sonic Racing, Kaos appear again along a single road segment on the Ocean View race track. Like in Sonic & All-Stars Racing Transformed, the Kaos can be found rolling across the road. If a playable character makes contact with them, they will literally get flatten, causing them to take damage and spin out temporarily.

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Main article | Gallery | Script (Console/PC, 3DS) | Beta elements | Staff (Console/PC, 3DS) | Glitches

Main article | Gallery | Staff | Glitches

Main article | Gallery | Script | Staff | Beta elements
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