1st game: Nim

Rules

Marbles are seperated into sets. Both players alternately take marbles from the table. When your turn you can take any number of marbles (even all of them), but you can only take them from the same set. The winner who takes the last marble.

Analyzis

This game is interesting because it has a concrete winning strategy, wich means: if you have the first turn and you use that strategy, you will always win. If the opponent doesn't use the winning strategy (thus screwing up the first turn), you always win.

Use in RPGs

You should not use such mechanics, because if the players will know the winning strategy, the game becomes boring. This game can be seen as an example of what to avoid. You should always make the game more complicated by using complex rules or by using randomization or by hiding information (you don't know what your opponent knows). (In fact the first to solutions are the hiding of information, too.)