taking an extremely big hit, preferably by using a steam roller. Bongs are acceptable. The hit will feel like an extremely large thc smoke is attacking your face, nostril, and throat. This causes 5 seconds of being stunned. Immediately following, you will see waves/levels of smoke in front of your face..thus resembling a swamp
we were passin it along smoothly until my friend sat stunned with a wierd look on his face, while smoke engulfed his face, he woke up and said "wow, that was a swamp hit"