Steel: Scrapyard guard dog reanimated by pieces of scrap metal
Dragon: Anatomically inaccurate Iguanondon with the nose spike (never really existed, hence the ghost type)
Rock: Mammoth with a stone-like body that paints on itself (reference to ancient cave paintings and modern elephants that paint with their trunks)
Water: Swordfish duelist that wanders the ocean in search for worthy opponents
Grass: Dead patch of wandering grass that searches for a suitable climate but is cursed to always be malnourished
Ground: Stegosaurus that has tombstone-like plating and a shovel-like tail, digs holes to rest in

Will finish the rest in the thread