Hippity hoppity this pokeball is my property

In the Osai region, there is more than one starter line-up. Pokemon Wave Version gives you the choice of Draggle, Lamburnt, or Marmink as a starter pokemon - this group is the Odyssey Trio, themed around Greek mythology. But pick up Pokemon Storm Version, and you'll get access to the Ken Trio, based off of a popular rock-paper-scissors style game from China and Japan. So starting us off is the grass type line:

Troad, the tiny toad pokemon
Troad is a very small grass-type pokemon from the Osai region. It lives in forests that get a lot of annual rainfall and fog - because it doesn't spend any part of its life in the water, it gets all of its moisture from the air and soil. Its hard skin protects it from drying out and from predators, and the moss that grows on it helps to attract prey and provides it with moisture. Troads can't jump very well and mostly get about by crawling, and will burrow into the ground to escape detection. Their bodies are so sturdy that you could stand on one without hurting it. When the vegetation on troad dries up, it is close to evolving. Troad evolves into ribbris at level 15.

Ribbris, the sporeback pokemon
Ribbris is a small grass-and-rock type pokemon from the Osai region. It lives in forests but can sometimes be found in meadows in the spring, looking for prey after a long winter spent hibernating. Their hard skin has broken into rocky plates thanks to the mushrooms growing on their backs - these special mushrooms form a symbiotic relationship with ribbris as it allows them to draw in nutrients from the soil just by being in contact with the ground. They use this extra energy to develop their powerful limbs, allowing them to jump up to three times their height after flying bug-types like enignat. They guard their mushrooms jealously from other ribbris, who will try to steal them for their own collections. They collect leaves on their backs to feed their mushrooms, and also to help keep their exposed skin moist. Ribbris evolves into toadynasty at level 36

Toadynasty, the sporeback pokemon
Toadynasty is a large grass-and-rock type pokemon from the Osai region. The mushroom growing from their back provides this pokemon with a curtain of spores that confuse and confound predators and prey alike. The mushroom now provides it with all of the moisture it needs, so toadynasty's skin has hardened to a rocky consistency again. It is a voracious predator and eats not only bugs but small rodents, birds, fish, and just about anything else it can fit in its wide mouth. The plants seen in their mouths aren't food, but some sort of intraspecific communication tool, the exact purpose remaining unknown. Toadynasties grow small mushrooms on their undersides and periodically shed them - this is how ribbris acquire their own mushrooms and so a single toadynasty is often followed by a group of ribbris "retainers", waiting to scoop up the next shed mushroom.