I want to build a tnt duper but there are spawners under the ground. Can tnt destroy spawner?
No, spawners are TNT resistant
No they are not!
Yes, TNT can destroy a MobSpawner.
Even Creepers can destroy MobSpawners!
A spawner has a lower explosion resistance than stone. Anything that can blow up stones can blow up spawners.
https://gaming.stackexchange.com/questions/74531/can-creepers-destroy-spawners
Hopefully I got there on time and you didn't blow up your spawner because of the other guy xD