What is the best prank you have pulled on a new butter bar?

I kinda miss abusing Butter Bars, lol

I had a 2LT, West Point Grad, who would not listen to me when I tried to keep him out of trouble. We were at NTC in training. I had spent 6 years in Mech Inf in Germany and learned to recognize the tanks by their engine and track sounds. The Opfor had Shermans and the attached friendlies had M60s and M1s. We were setting in a defensive position one night and a couple of M60's pulled up in hull defilade about 200 meters from our position. He decided to take a M60 MG and a couple of LAWS and attack them. He didn't believe me when I told him they were friendlies and went anyway. He got "KILLED" and I spent the next three days leading the platoon.

I actually convinced a second lieutenant that pick up the batteries in the compass needed to be changed. You flip the compass over and start removing the four screws that held the compass together. I just walked away and everybody else just burst out in tears.

In 1986 I was demoted from sergeant to 2nd lieutenant… I think because I was a Mustang my troops never put me through any of this. Here is my advice to very junior NCOs who screw with 2nd lieutenants. Be careful that the toes you step on today are not connected to an a** you have to kiss tomorrow. Lieutenants grow up to be captains, majors, lieutenant colonels, and beyond. If you go too far, or they don't have a sense of humor, your career could become a bit miserable in the later years.

Some more elaborated than other but it the simple ones that to me are funny.
LT wanted to take the jeep so I gave him the key to a safe and told him it was the "key" to the jeep. This was at a BN HQ - the BN COL thought it was hilarious we all watch as he sat there for a good 30 minute before he came back in - "Hey, where's the ignition?" I made sure I got the key back before I showed how to start it.

We used to send cherry Lts to get the keys to the drop zone

I was working in an ADA unit in Korea. Launcher crew had someone stand behind the launcher with a fire extinguisher and let it go when the new LT was doing an inspection. All the soldiers started screaming and running. They made it a few feet. The LT ran right off the site thinking the launcher was about to go off.

Had the Lt go to the toolroom to pick up a bucket of track tension for the M113s troop carrier.

Sending the Lt. to the motor pool sergeant to get a box of track tension.

Saluting, left handed, then chewing him out.
As CPT (03) pretending to be guard on post at night then getting them to spill their guts on how they feel about the old man. So funny watching upon through reveal