what would you reccomend as a trip killer for lsd?

will be using lsd soon , never had a bad trip but have had challeging ones , what would you reccomend as a trip killer if things go south? i have access to olanzapine pills dosed at 5mgs , and a single 2mg kpin , i would want something that would completely kill the trip (both the visuals and headspace), and i might even just use it to end the trip prematurely since it will be my first time tripping in public and a 12 hour trip since like too much of a commitement , which one would you recommend for ending the effects of the acid , and at what dosage , thanks in advance!