Found a group to play around October last year. I started my character and one of the DMs for the group was running the Stranger Things module for new characters. We get through to the "upsidedown" and have to deal with mr big bad but not the main bbeg. So we laid a trap, had a ranger set a snare trap and rolled a natural 20 when constructing the trap. Had someone that could set the bait with some ability that could also amplify the effect. We split into separate cardinal points and hid, everyone rolled above 17 for stealth, dm said we all hid well enough. Big ugly takes the bait and when he hits the trap, it snares him perfectly, dm rolls his checks and says even with the perfect snare it doesn't look like it will hold for long (we figured 1 maybe 2 rounds). We charge in to attack. First player in crit on the attack. Next player in didn't crit but did max damage. The next 2 players role crits and almost max damage. I rolled high and almost max damage and the final characterthat attacked rolled crit as well. We ended up bringing it down in one round. The amount of 20s rolled in that round was insane. Even with the plan had we not rolled so well he probably would have managed to get out and killed at least one of us. I was pretty proud of my plan and since it was my first time playing with this group I think it impressed them some as well.