Lesson 9 - Dark & Steel Pokémon
Dark typed Pokémon were introduced to help balance out the types, particularly by being effective against Psychic Pokémon. When paired with a Ghost type it is the only type to have no weaknesses. Dark moves are super-effective against Psychic and Ghost, but are not very effective against Fighting, Dark, and Steel. Psychic Pokémon have no effect on Dark types and Ghost and other Dark types have little effect. Fighting and Bug Pokémon are super-effective against Dark Pokémon. Despite being introduced late there are still 39 different Dark Pokémon.
purrloin - liepard
Purrloin can stand on their hind legs and walk around, and they have a liking for stealing things. They are very charming and cute, and use this to their advantage. Even when caught taking things red handed, they often get away with it because of their charm. Liepard are very attractive Pokémon that can appear and disappear at will. They use this stealth to track down opponents and attack them before they expect it.
Steel Pokémon were also introduced in the second generation, and have the highest average defense stat in the game. 11 types are not very effective against it, and Poison has no effect, so the other types that do well against Steel Pokémon are Electric Types as well as Fire, Fighting, and Ground which are all super-effective. Steel moves are super-effective against Ice and Rock Pokémon, but are not very effective against Fire, Water, Electric, and other Steel Pokémon. This type has 38 Pokémon, which are discussed below.
aron - lairon - aggron
To make its body, Aron eat iron ore that they dig up in mountains, and have been known to eat bridges and railroads while it tries to grow. Lairon nest near mineral water and eat rocks that contain iron to build up their strength. Aggron are very fierce and aggressive Pokémon that will claim entire mountains as their territory. If their territory is destroyed from a fire or flood they are known to bring back in top soil and start planting trees and plants to regrow it.