Koh Samui magic mushrooms are a very popular strain hailing from the Island of Ko Samui, Thailand.  Found in the town of Hua Thanon by well known ethnomycologist John Allen .

Ko Samui mushrooms are characterized by short and fat stems, caps can occasionally be very large and turn red-brown as they age.

This psilocybe cubensis strain is typically very potent and known to produce strong visuals.  Expect similar effects to Penis Envy.