Light Grenade

The Light Grenade or Flashbang is a weapon found in both ObsCure and ObsCure II. It's a fairly rare weapon, specially in the first game. In real life (and other games), it's a non-lethal explosive device used to temporarily disorient an enemy's senses, but since ObsCure's monsters are weak to light, this is one of the most powerful weapons, as multiple enemies can be killed with just one grenade.

ObsCure
The Light Grenade is the only weapon that can be thrown. In ObsCure only 4 light grenades can be found in the entire game, and only after you've gone through the first set of underground tunnels. It takes three seconds between being thrown and the moment of the explosion for a powerful flash to flood the area. Because the Mortifilia weak to light, the sudden flash of light will usually kill all enemies on-screen, regardless of their strength and endurance, and how close they are. This weapon is best suited for groups of difficult enemies, like the two ArbolTrebols found just after finding the first grenade.

ObsCure II
In ObsCure II you will find some flashbangs in different parts of the game, starting from Fallcreek's Dam.

The Flashbang generates a flash for a wide area that almost instantaneously dissolves all the little monsters and some of the big threats, even if a creature survives the explosion, his health will still be dropped dramatically, given the Mortifilia's strong repulsion to light. The grenades are a bit more common here, if you don't have any, the game may drop some on the random boxes you can find scattered around.