Walkthrough
After both your and your Rial have selected your Starter Pokemon, Professor Oak will send you each on your way. However, as you attempt to leave the Pokemon Lab, your Rival will stop you and challenge you to your first Pokemon Battle. Do remember that your Rival will have selected the Starter Pokemon that resistant to your Starter Pokemon; however, since both of your Starter Pokemon will be at such a low level and will only know neutral attacking moves, things will be on an even playing field.
Rival (Bulbasaur Chosen): Level 5 Charmander
Rival (Charmander Chosen): Level 5 Squirtle