In pokemon we see water beats fire, grass beats water, fire beats grass, and ground beats fire. This balance works very well. In advance wars we see artilary beating planes and tanks beatig artilary. Having a rock, paper, scissors mechanic in your game will almost always work. When you try and make everything equal things will get messy. There needs to be a clear way on how to beat something. Players need to know how the computer can counter their moves aswell.  If we throw a little randomness in the gameplay players will really have to use skill to win. For example if a pokemon trainer just braught out a charizard you need to be ready and have atleast a thunder, or water type waiting. If not the player has to make the choice of bringing out a pokemon that is not weakeer or stronger than the opponent. This would end up in a dog figt.

Dog fights are a good way to test skills aswell. Players should manage what ever rescource they have in order to win. Since brute force isn't an options players have to strategize on how to attack an equally matched cpu.

What ever tools you give the players should be enough for them to defeat the enemy.

Poor decisions = poor outcome.

There needs to be a best decision in any scenario.

The problem also occurs when players get an uper hand when buying items from cash shops. I spoke on this before and it can indeed ruin gameplay. Just Imagine if a player could give his pokemon +500 HP by buying nintendo points from their website. The rock, paper, scissors mechanic would be partially destroyed because it wouldnt matter if the player is outmatched. They have extra HP.

Balance is always key to having an effective fun game. Having a rock paper scissors mechanic will strengthen any game.

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If you want more examples of this mechanic check out:

Final Fantasy X

Pokemon

Advance Wars

Fire Emblem

Plants Vs. Zombies

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