Here's a creeper farm with over 1700+ gunpowders per hour. Works in 1.20+. Initially designed by @MushoDen with a bit of modification.

✔ What you will need to build this farm:
1161 Building Blocks
994 Slabs
852 Trapdoors
21 Fences
8 Fence Gates
12 Buttons
88 Carpets
64 Scaffoldings
9 Hoppers
6 Chests
1 Bed
9 Soul Campfires
8 Carved Pumpkins
16 Snow Blocks
8 Water Sources
Temporary Blocks

⚠Important:
When building the AFK platform, do not build up over 120 blocks as mobs despawn immediately if they are 128 blocks away from the player.

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Chapters:
0:00 Intro & Material List
0:23 Location
0:33 Collection & Storage System
1:10 Killing Chamber
4:34 Spawning Platform
6:15 Ceiling
7:10 Soul Campfires
7:29 AFK Platform
7:54 Outro & Results

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