Espio: Master of Camouflage is the fifth and final Challenge Act of Speed Highway Act 2 in the console/PC version of Sonic Generations. It is unlocked after clearing every Stage in the Dreamcast era and is playable only as Modern Sonic.
This Challenge Act, except for its final section, is modeled after the first 2.5D section in Speed Highway Act 2 and starts from when the player enters their first building.
In this Challenge Act, the player must run through the course as usual, except at certain intervals, Sonic will be halted by Espio. The area will then be closed off by Cases, and Espio will turn invisible using Ninja Arts: Camouflage. Sonic must then dodge the shurikens that Espio hurls at him and make his way to a local searchlight. To turn a searchlight on, the player can hit it with either the Homing Attack or a Spin Jump. Should the searchlight's beam pass over Espio, he will reappear and be stunned briefly for the player to attack him, upon which he will be knocked down and disappear while the Cases are lowered. If Espio is not attacked in time, he will turn invisible again and the process will repeat.
When starting this Challenge Act, the player must go down a corridor into a shaft where the first face-off with Espio begins. After clearing it, they must follow the path to the bottom to reach Espio again. The player must then clear this section to enter the shaft on the left and the next face-off. This section takes place across platforms, making it trickier to get a fix on Espio.
From there, the player should go to the bottom of the shaft and follow the corridor across a narrow bridge in 3D. Once past this section, they need to scale the platforms to reach Espio again. Here, there are two ladders-like platforms which make it even trickier to evade Espio's attacks and get a fix on him. From there, reach the next section by skipping across the Spinners on the right. The player will then have two successive face-offs with Espio in narrow spaces which Espio can easily hide in. After them, the player can reach the final section via the route on the right. The final section is the largest and filled with yellow platforms that flip at regular intervals. This section is also nearly split in two, making it easy for Espio to hide and hard for the player to target him. After that, the player can access the Goal Ring.
- This is the first Challenge Act in which Espio the Chameleon appears.