You might wonder why not just buy Blue. Well, some PokeMon can only be caught in Red. These PokeMon are Sandshrew, Meowth, Bellsprout, Victreebell, Ninetales, Sandslash, Persian, Weepinbell, and Vulpix. There are also PokeMon that you can only find in Blue. To get those names read the review for Blue.

You can only carry six PokeMon at a time, and any of them can battle against wild PokeMon or other trainers. When a PokeMon that you were fighting faints, each of your PokeMon that fought in the battle are given experience points. For example, if defeating a wild Growlithe is worth 30 experience points, and one of your PokeMon fought in the battle, it receives the 30 experience points. If two fought, they each get 15 points, and so on.

As a PokeMon collects experience, sooner or later it will get enough points to move up to the next level. At some levels, a PokeMon is given the opportunity to learn a new ability. A PokeMon can only have four abilities at a time, so it may need to get rid of an ability before it can learn a new one. You can also teach you PokeMon Technical Machines and Hidden Machines so they'll learn abilities that they wouldn't normally get by growing to higher levels. Some PokeMon evolve into new and better forms when they reach the right level. When a PokeMon evolves, you get credit for catching it.

Collecting experience isn't the only way that a PokeMon can evolve. Some evolve when you use certain stones on them. For example, if you use a ThunderStone on Pikachu, it will instantly evolve into Raichu, no matter what the level of it is. There are five stones, the Moonstone, Firestone, Thunderstone, water stone, and leaf stone. Each stone only works on certain PokeMon.

PokeMon are divided into 15 types. Each type goes with a particular ability, set of characteristics, or physical property. For example, all water type PokeMon either have abilities related to water or live in the water, while fire type PokeMon have abilities related to heat or fire. Each type has weaknesses and strengths. This affects how a PokeMon performs in battle. For example, a fire-type's characteristics give it a natural advantage in battle against grass-type PokeMon. On the other hand, these same characteristics make a fire-type vulnerable to a water-type PokeMon.