Sideboard

Okay kiddo, so you know how when you play a game like cards or a board game, you have a group of things you can use to help you win, right? Well, in some games there is something called a "sideboard". It's like having a secret stash of things you can bring out to help you win the game, but you can only use them sometimes.

Let's say you're playing a card game and you have a bunch of cards in your deck. Your deck is like your big group of helpers that you can use to try to beat the other person/ team you're playing against. But sometimes you might have some really cool cards that aren't good for every game - maybe they only help you against certain kinds of opponents. So instead of putting them in your big group of helpers, you put them in your sideboard.

Now, during the game, you get to look at your sideboard and choose some of those special cards to switch with some of the cards from your big group of helpers. It's kind of like taking a timeout in the game to go and get something from your secret stash. But you can only do it a few times during the game, so you have to be really careful and choose the best cards to help you win.

That's the basics of what a sideboard is. It's like having a secret stash of helpers that you can use to try to win the game, but you can only use them sometimes.