Use the left/right arrow keys or the A and D keys to steer the ball left or right. Along the way, you'll encounter various types of obstacles such as Treblocks, Tunnels, Verts, Snakes, etc. Every kind of obstacle requires a bit of technique to overcome. For example, when passing through a tunnel, you must ensure the ball stays in the center and doesn't touch the red blocks inside. The game has no finish line - your goal is simply to keep the ball moving as far as possible.
If you're a fan of adventure games, you might also enjoy Hollow Knight Silksong.
Compared to Slope 3, the graphics of Slope Plus more closely resemble the classic Slope game. The combination of green and black colors, along with red obstacles, creates a fitting environment. Although the two versions differ in terms of visual style, other features such as gameplay and obstacles remain largely the same. However, in my opinion, the ball in Slope 3 moves slightly faster than in Slope Plus.
Green and black graphics in Slope Plus