Something that you say you or your friend is on/smoking when he says something crazy, weird, outlandish, or if you're anxious/freaking out about anything.
"He just said the craziest thing ever, he must be on that tweaknine pack."
or
"Istg I'm on that tweaknine pack I cant stop thinking about her."
The tweaknine pack makes you do, say, and think things not even the devil would think of doing.
Something you say someone is on/smoking when they say or do something crazy, outlandish, weird, or all of the above.
Could also be used to refer to weed that makes you anxious/paranoid.
"No shot he actually went and threw schorching hot honeybuns at homeless people, he must be on that tweaknine pack."