Cannabis firms Sundial Growers and Tilray both jumped more than 30% at the beginning of the US cash session. Other pot stocks, including Aphria Inc (+12%), Canopy Growth (+12%), Aurora Cannabis (+12%), and Organigram (+27%), saw tremendous gains at the open. 

ETFMG Alternative Harvest ETF, otherwise known as the pot ETF, has nearly doubled in price in a few weeks.

Before Tilray erupted, the short interest in the stock was around a quarter, giving r/WallStreetBets a good enough reason to pile into it and pressure the "suits" who are short.