Buy Koh Samui Magic Mushrooms, also known as Psilocybe Cubensis Thailand Koh Samui, is a popular and old-school strain from the beautiful island of Koh Samui. The Koh Samui is known to be very resistant to contamination and is a very fast colonizing. The Koh Samui shrooms grow distinctively with very thick mushrooms, it does not grow very tall but what it lacks in height it makes up for in thickness.