(Another) Valentine's deal alert! 3 Core Studio's physics-cheating, first-person puzzle-platformer Pulse Shift is half-price today only at Desura. A free demo version is also available.

Pulse Shift presents a wide variety of first-person platforming challenges in which players can shift gravity and manipulate time, with dizzying results. Your abilities range from simple stuff like platform slowdown and wall-walking to the full-on reversal of gravity and time itself, and with over 60 included levels, you'll have ample opportunity to test the limits of the game's unique mechanics.

Pulse Shift is regularly priced at $9.99.