Some of the games on slopeunblockedgame.com need Flash. You need to allow it above.
If you don't see the Flash option above, you can still enable Flash as follows:
Flash is a multimedia platform used for browser games, videos, and other rich internet applications. Every game on CrazyGames is thoroughly tested and checked for viruses and other threats, following our strict content guidelines. This is why you can be absolutely sure that playing Flash games on slopeunblockedgame.com is completely safe. If you have any questions or concerns, feel free to contact us.
If the Allow button is not appearing, make sure to wait until loading the page is finished. If it's still not working, reach out and let us know which browser and which version of it you are using.