Roselia (the Thorn Pokemon) is a relatively common Grass/Poison-type Pokemon found among grassy plains and forests within the Hoenn, Sinnoh, Unova and Kalos regions as well as the Kanto and Johto regions on rare occasions. Though these petite little creatures may appear to be quite beautiful and elegant, Roselia are feisty plants that can certainly give their opponents a raw deal in close-quarters confrontations. Sure, they might smell nice and release soothing fragrances that are to die for…but if you get too close to their poisonous thorns, that's exactly what you might end up doing!
The flowers on Roselia are recognized world-wide for their incredible beauty and elegance, hence the popularity of these Pokemon in Contests. The coloration of the flowers is mostly dependent upon the water that Roselia drink; the cleaner the water, the more vivid their coloration. In addition to being beautiful, the flowers are also valued for the fragrance given off by their pollen; unlike the toxic pollen possessed by Budew, Roselia pollen is extremely efficient at relieving common ailments and symptoms. How the pollen is actually able to do this is still a bit of mystery, but it appears that it heightens the immune response within life forms that breathe it in, helping to fight off infections and diseases at an accelerated rate; as such, the Aromatherapy technique of Roselia is highly potent. In battle, this can prove to be advantageous for Roselia, as the scent of their flowers relaxes foes and makes them careless, giving Roselia the opportunity to strike with their toxic thorns. Although they are quite small, Roselia are made extremely dangerous in close-quarters battles as a result of the toxic thorns hidden within their flowers. Much like normal roses, Roselia contain many small thorns within their flowers (in addition to the three large ones on their heads); these thorns are directly connected to their nervous system, however, allowing Roselia to manipulate them and fire them at opponents. The toxins contained within the thorns are among the strongest in the world and can be more than lethal if too much is injected into an opponent's bloodstream. Moreover, each flower-arm of a Roselia contains a different type of poison; their blue flowers are filled with paralyzing toxins while their red flowers are filled with neurotoxins. The reason for this differentiation is not known, but it is possible that Roselia purposefully possess two separate types of toxins as a way of minimizing the number of life-forms they accidentally kill with their toxins (as paralyzing toxins are much easier to cure than neurotoxins). As such, it is a very bad idea to get close to a Roselia without heavy armor or protection, as the thorns are capable of penetrating soft flesh with ease.
Roselia also hold a very special honor among Pokemon: They were the first Pokemon recognized in written history to possess a shiny variety. Shiny Pokemon possess unnatural coloring that occurs as a result of random mutations within their cells; such mutations are incredibly rare, hence the value of shiny Pokemon among collectors. Roselia are particularly prone to such mutations when exposed to extremely rich sources of spring water; the exact cause behind this occurrence, however, is still the subject of some debate. Regardless of the cause, it seems that the beauty of Roselia was admired just as much in ancient times as it is today; since special attention was often paid to them in the form of exotic sources of clean water, it's easy to understand why they were the first Pokemon noticed to occasionally display strange coloration.
Even though they might not be the most powerful Grass-type Pokemon, Roselia are still dangerous creatures that can easily subdue even the largest of opponents with a few pricks from their thorns. If you enjoy nature and want to carry a little part of it with you at all times, you won't get much better than a Roselia; their brilliant flowers and enticing aroma should be more than enough to send you into a relaxing daze, even during the most stressful moments of your day. Just don't think about picking their flowers for a special someone; they might be small, but that certainly doesn't make their deadly Toxic technique any less dangerous!