Pokemon Tower Defense is one of those things you look at both with apprehension and a sort of guilty longing. The game, by Sam and Dan, is exactly what it sounds like; the popular gotta-catch-em-all experience turned into a fan-made tower defense RPG hybrid complete with goofy story, evolution, trading, Mystery Gifts, badges, and more. It's a surprisingly fun, addictive, and even strategic little game that fans of the series will want to sink their teeth into.
You set your lineup before each stage, and then drag and place them to squares on the battlefield where they'll attack anything in range.
You can also adjust your Pokémon placement on the fly, grabbing and dragging them around to any other open spot on the map if you need to make a change to your strategy.
Generally, the most effective attacking types are Psychic, Fighting, Ground and Ice. Defensive types to watch out for include Rock (try Water, Fighting, Ground, Ice or Grass), Ice (try Fire, Fighting or Rock), Dark (try Fighting, but don't use Psychic!), Dragon (weak only to itself and Ice) and most notably Steel (Fire, Fighting and Ground work while very little else has any effect). Also watch out for Ghosts, which are completely immune to Normal attacks like Tackle.
For instance, if you start with Bulbasaur it'll probably learn Vine Whip by the time you enter Viridian Forest. You might be tempted to use this new ability, but if you do you'll have rendered Bulbasaur useless against the bugs you're battling! Instead, try using Vine Whip during your first gym battle, where it'll deal heavy damage to the Rock and Ground monsters you'll fight there. You'll win with ease.