How to force someone to twitch uncontrollably and excessively for around half an hour?

[⚞⛇⚟]

Pretty spooky halloween prank.

 

[Poppavalyim Andropoff]

tongue their balls violently

 

[We Are The Witches]

Tickling!

 

[dick brain]

When they nut you keep sucking.

 

[Soy Fed]

African scientists have done it with a car battery. There are some demonstration videos on kaotic.com. What an exotic name for a website.

 

[Jason Wynn]

Tickle them? Keep touching them with an electric hand buzzer? Barely touch the back of their neck?

Or you could go with @Poppavalyim Andropoff idea of tonguing their balls. Always gets a reaction.

 

[Gangstalker #32194]

meth

 

[PointOfNoReturnPoint]

tongue their balls violently

Their is no better answer than this, at all. Maybe do it on a unicycle if you have one.