A switch blade is a knife or a type of blade which gets folded or slided in the handle and can be opened automatically by pressing a button.
A grenade is a small bomb typically thrown by hand. Mind you! Throwing a grenade up stairs is dangerous, due to the risk of it falling back down; it is much safer to throw a grenade down stairs. Do you know it can also be made to release smoke, tear gas and other gases, as well as illumination? This tutorial contains plenty of useful tips on how to draw grenade.
