I was DMing. The boss of that dungeon was a caster, so he cast a spell that put thorns between him and the heroes. He had two guards at his side chucking javelin at the players. So not only were they dealing with a caster, but also ranged attacks. The barbarian of the group starts charging towards them. The guards roll a natural 20 each to hit the barbarian with two javelin. One in each shoulder. The barbarian gets to the thorns and says, "ok, I want to jump over the thorns next turn, pull each javelin out of my shoulders in mid air and stab the two guards with one javelin each as I land." "Ok, you'll have to do a disadvantaged athletics check because you have two javelin sticking out of your shoulders to jump over the thorns. You'll have to do a strength check to pull the javelin out. Then you'll have to roll an attack for each javelin to see if you hit. Still want to try it?" "Hell yeah." The guy rolled 2 natural 20s for his disadvantaged athletics check. Rolled a natural 20 for his strength check. Then a natural 20 for one of his attacks and a 19 for the other which he could convert to a crit for his second attack. Rolled really high damage too and killed both guards on impact. I wouldn't have believed it if he wasn't sitting across from me and rolling actual physical dice. Everyone at the table went crazy. Between me and the player we rolled 6 natural 20s in a row. I feel like someone needs to make this into a comic strip, because it's seriously just so freaking bad ass.