This machine has 5 stages:
1 - Warden is lured by the player to the machine, that traps it into the hole.
2 - Uses TNT to launch the Warden up from the bottom of the map to Y level 200.
3 - When reaching the top part, a slime and piston combination pushes it to the side.
4 - Uses more TNT to accelerate the Warden downwards. This is not required to kill the Warden, it's purpose is to speed things up.
5 - The Warden lands on a pointed dripstone, and dies.
In total 52 TNT is used. 40 in the first stage, and 12 on the second.
The machine also has a system that helps to trap the Warden, that uses pistons and pressure plates.
To send the signal to the top part, i used a bubble column + observer, since it's delay is constant, not being affected by distance.
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Made in Minecraft 1.19.