Carfentanil 

Under the brand name Wildnyl

A super concentrated form of Fentanyl

10000 times more potent than Morphine

and

100 times more potent than Fentanyl

used to sedate large animals

We will now feed the 1000 pound bear with a microgram of Carfentanil to put it to sleep.

Carfentanil by ThatGuyFromLikeThatConcert3YearsAgo February 1, 2008

Carfentanil 

The most powerful opiate narcotic known to man. 5000x as powerful as pure herion.

The park ranger accidentally killed the elephant with a carfentanil overdose.

Carfentanil by John Mann January 12, 2005