If you were to get a sculk shrieker with the block state of: ‛can_summon="true"‛ in a flat world that block won't shriek when you try to activate it, thus it won't summon a warden, unlike in a normal world.

You can reproduce this bug without using an external programs making it Mojang's issue to fix and not mine.

This bug affects map makers and skyblock/flatworld players

How to Reproduce in Vanilla:

• Create a normal creative world
• Type the command: /give @s structure_block
• Find a deep dark biome and locate a skulk shrieker
• Place the structure block near the shrieker and make sure it's inside the bounding box
• Give the structure a name and click Export
• Put the .mcstructure inside a behavior pack in the "structures" folder
• Install that behavior pack on a flat world and join it
• Loud the structure by its name using /structure command or a structure block
• Step on the sculk shrieker or give it a signal by a sculk sensor

How to reproduce with external programs

• Install Amulet
• Create a flat world and place a sculk shrieker
• Open the same world and with Amulet
• Select the 3D Editor menu
• Select the sculk shrieker with the left mouse button
• Click Operation in the bottom of screen and select Replace
• Select sculk_shrieker and change the propriety value of "can_summon" to "1b"
• Click Run Operation and save changes
• Go back to Minecraft and step on the sculk shrieker or give it a signal by a sculk sensor

The expected result:

   The sculk shrieker shrieks

The observed result:

   **   Nothing would happen

Please do your best to fix this issue and other issues related to flat worlds like MCPE-147078

Thanks for always listening.