Ok, so this one is nothing new, it has been doing the rounds in China for several years (at least)! But I thought it was about time it had the Matt-Erials treatment and a bit of an upgrade! And it's a great one to use as a review of vocab, or even grammar.
Split your class into a number of teams (two can be good, but more is better) and show them the black and white screen. A member of each team comes to the front and clicks on a word. If it is on a black square they have ten seconds to define the word. If it is on a white square they have ten seconds to use the word in a sentence. If they are correct (for either one) they can click on the square again. And then the fun begins!
If they reveal a knife, they can "kill" one person, of their choosing, from another team. That person is then out of the game (for the time being)!
If they reveal a revolver, they can "kill" two people, either from the same team or different teams. Those people are then out of the game (for the time being)!
If they reveal body armour they are safe from being "killed" for a specific amount of time (I usually go for one round, you can choose more if you want).
If they reveal a first aid kit they can save one member of their team at any point. Again, you can put a time limit on it if you want.
But, if they cannot define or use the word before the timer finishes that player is "dead". They can be saved by the first aid kit, if they already have body armour, they are safe and can keep playing.
Don't worry, all the rules are on the second screen of the game, just to help you!
I have provided five different boards, the locations of the weapons and "saviours" are different for each one. All you need to do is add your own words from the course you have been teaching. It works well for slightly older groups, I wouldn't use it with anyone below about the age of 7 (they might not quite get the idea behind it). And bigger classes are better, the more teams the more competition.