@umjen so a lot of japanese mobile games have a "gacha" system where it's random chance that you'll get an extremely rare unit when you summon or whatever. (Think pokemon as an example)
They usually have rankings such as N - normal R - rare SR - super rare and the list goes on. The higher the ranking, the better the unit, and usually the best graphics are on the highest ranking cards. Some games go up to SSR - super super rare, but others have UR - ultra rare or some variation.
So an SSR Bulbasaur would normally be considered better than a SR Pikachu and would have better design. It depends on the game though lol!