The mechanic was made by Game Developer rootpilot.
Game Developer, known as rootpilot, continues working on an upcoming game and showing us new mechanics from it. This time, the developer set up a cool spear-like movement tool that can be thrown at any wall you want and used as a grappling hook surface, allowing you to quickly swing towards any wall or floor. The mechanic, according to the developer, will be added to the game after some improvements.
In case you missed it, rootpilot has been developing the game for more than two years as a Solo Game Developer. As of right now, the game doesn't have a name, a genre, and a release date. However, the author regularly posts development updates that show that it will likely be a late 90's-style shooter with tons of stunning movement mechanics.