It's actually been awhile since I've played Egyptian Rat Slap (too many injuries, we had to halt play partway through the school year), but I think I remember how to play it...
It's sorta a combination of War and Slap Jack really. The point is to get all of the cards in the deck. To begin, you split up the deck so everybody gets cards. You don't look at your cards. You go around the circle laying down a card, face up, in the center (flip from the top of your deck and away from you so you don't have the advantage of seeing the card before the opponents

). Whenever an Ace is played, the next person in line has four chances to lay down a face card on the pile. If the player doesn't happen to have a face card in the top 4 cards of their pile, the player who played the Ace picks up all of the cards in the pile (all the cards below the Ace and the 4 cards on top of the Ace). Similarly, with a King you get 3 tries to produce a face card, with a Queen you get 2, and with a Jack you get 1 try. Anytime the player fails to produce a face card, the player of the original face card is awarded the pile. If the person DOES produce a face card, the game continues. For example, the third card I lay down on your Ace is a Jack, you don't get any cards, but I do

because the person who plays after me happened to lay down a 2(a non-face card). (is any of this actually making sense?) Now for the "slap" part of the game...When doubles get layed down, the first person to slap the pile gets all of the cards. Example: I lay down a 5, and the next card flipped onto the pile is also a 5. Well, I, being the keen observer I am, notice this before anyone else, so I quickly slap the pile first (and then some girl wearing these big rings which apparently slows down her swing, slaps my hand hard, smashing the rings right on top of my knuckles, and I scream "ouch!" but smirk because I still get the cards

) Anyone can "slap in," even if they've already lost their cards. Some people also play that you can slap "sandwiches." Sandwiches are cards in sequences like 5-8-5 or 3-6-3 or 9-2-9 or 7-4-7...I think you get the picture. As with all games it seems...there are variations and other little rules that don't pop up until you're in the middle of the game, but these are the basics...If you can call it "basic" with the amount that I actually typed. I guess it remains to be seen if what I typed makes any sense anyway.