Pokemon Tower Defense 2: 1 vs 1 Levels 1&2&3

Level 1

Level one is as simple as deploying your first Pokémon, ensuring their primary attack is active, and observing the battle unfold. Caterpie's secondary attack, 'String Shot', decreases the opponent's speed, useful for future battles. Defeat Oak's Pokémon using your primary attack alone, then move on to Veridian Forest with your 20 coins.

Level 2

Now you can purchase Rattata to strengthen your team for the next, more challenging battle. Optionally, buy Oran Berries, Potions, or a Rare Candy to level up your Pokémon. Use Rare Candy 1 to level up Caterpie, making it easier to defeat Bug Catcher's Weedle and Metapod. Use Rattata's Quick Attack to defeat Beedrill and win Level 2.

Level 3

Choose between Pidgey and Spearow to add to your team. Purchase potions for caution, then proceed to battle against Ash Catch'em, starting with his Caterpie. Level up your Caterpie with Rare Candy 2 to evolve it into Metapod with Harden. Defeat Pidgeot using sand attack with Pidgey, then tackle Pikachu to win the battle.

Congratulations on defeating Ash and unlocking Nidoran and Pikachu!

Note: Strategies may vary. This walkthrough reflects one possible approach.