Fellow 90's kid-pyro checking in. I remember when my father finally found my stash of black powder, metal tubing, various makeshift cannons, and flammable chemicals. Didn't really get in trouble--he was relieved it wasn't something as dangerous as weed.
Among destructive devices built as kids in the 90s, I think our crowning accomplishment was the Thermite we made as teenagers... only possible thanks to my friend who was somehow able to acquire a big block of Magnesium. I provided the Aluminium baseball bat ;) We got lucky that it fizzled out partway through (maybe from hitting dirt?), but his parents were definitely not too thrilled about the nasty hole in the concrete patio.
Moldy? Psh, that's nothing. The real excitement begins when you play with the sweat coming off the dynamite, like we did back when I was a kid in the 80s!
Note: the above is sarcasm. "Sweating" or "weeping" dynamite is dangerous and you should immediately leave the area and contact your local equivalent of 'the bomb squad' to report it.
Over time, regardless of the sorbent used, sticks of dynamite will "weep" or "sweat" nitroglycerin, which can then pool in the bottom of the box or storage area. For that reason, explosive manuals recommend the repeated turning over of boxes of dynamite in storage. Crystals will form on the outside of the sticks, causing them to be even more sensitive to shock, friction, and temperature. Therefore, while the risk of an explosion without the use of a blasting cap is minimal for fresh dynamite, old dynamite is dangerous.
I had a pyromaniac phase. Once set a field on fire. Things could have gone extremely worse.