When I was 12 or 13 I ordered a blowgun from the back of a comic book. The 6' Jivaro...."so powerful this man killed a 35lb. anteater". I was never sure why someone would want to kill an anteater but I had to have it. Several weeks later I was outside when the UPS truck pulled up and the driver pulled out a 6' long box. I vaulted over a retaining wall and a chaise lounge to get to that truck. That started my love affair with UPS drivers, AKA "brown santas".
That blowgun was a hoot. Had to make my own darts by boiling a string of plastic beads to pull them off the string, cut the needle wires to length, heat the tip of the needle with a propane torch and melt it into the bead. You young uns with your fancy schmancy pre made darts don't know how easy you have it.
The first time I showed one of my friends the blowgun we were shooting it at my phone book target across the living room and down the hallway. He didn't think there could really be any power because of how easy it was. I told him I could shoot it through a 1/2" piece of plywood and he just wouldn't believe it. I walked to the target and retrieved the darts. I had just turned back around when he shot me in the thigh. It didn't really hurt, but I could tell it was deep. "Jeez Larry, what are you doing? I yelled. A conversation ensued with Larry saying it didn't really hurt and me trying to convince him it was in my leg pretty deep. I couldn't really walk because it had pinned my bluejeans to my leg. Larry wouldn't come over to look because he was now sure I would grab the blowgun and shoot him. I finally took a partial step towards him and he jumped back and shot me in the leg again - this time about an inch higher than the first. This time I told him if he didn't put the blowgun down and come over to look, I was going to pull the darts out and kick his ***. He came over and watched, wide-eyed while I pinched the dart and pulled 2" of needle out of my leg. The second one was also in about 2", he felt pretty bad and apologized with the excuse that he didn't blow very hard.
I've had several through the years since then, but that one was the best. My others were a 2 piece, a 3' and a 2'. Get the longest. It's awkward, but the difference in power is enormous, and it's much easier to shoot with accuracy.
Post Script: A few years ago for Chistmas, I got several of my nephews the little 24" blowguns with the all plastic "safe" darts (no needle at all). They ran wildly around the house shooting each other and hollering maniacally. When they finally had enough they sat around comparing welts. That cemented my reputation as the cool uncle.