repeat steps

Adjust the game level to Easy or Hard and summon warden and golem and watch them fight.

Observation results

When you change difficulty the game to Easy or Hard, the warden will only have 30 damage as normal difficulty damage (hit the golem 4 times and it die).

The results should be

When adjusting the difficulty level to easy warden will have 16 damage (hit the golem 7 times and it die)

When the difficulty level is changed to Hard, the warden will deal 45 damage (hit the golem 3 times and it die).

This problem doesn't just happen to wardens, it happens to "all mobs or bosses in the game that deal damage".

In the video I adjusted the difficulty to easy, hard and the warden has the same 30 damage (hit the golem 4 times and it die) instead of the damage changing depending on the game's difficulty.