Things you need to do before starting:
When you spawn in, you will see three buttons on top of command blocks. Press those three buttons, then see the blue doors on the wall. Open them and walk through, then press the other button on the command block. Final thing you need to do: Follow the redstone into a hole, walk down the hole, then make sure the redstone is connected to the dispensers. Fly to the top, go through the blue doors again.

Playing:
Go into survival. Collect resources. Next, dig underground a 10-15 blocks+, then build a protected area. Go to the surface. Go back through the blue doors, the flick the lever on, then off quickly. Go back through the doors, get to safe house. When the white bar at the top is gray, the explosions are happening. Newest snapshot required. Try to survive! Maybe even challenge yourself against time! Maybe do it with friends! A beefy computer required, as 64,000 blocks of TNT explode.

Rules:
Survival, stay in the bedrock square, do not stay on the surface when the TNT explodes, no cheats, and have fun!!!!!

Made by SpireSight

Video of this in the comments

You can download this and put in in your worlds, but you would not be able to play until the 1.17 comes out, snapshot: 21w13a