I wish that Mojang added a new nether monster, only spawning in the nether.

I suggest an extremely powerful Nether boss. Mojang would choose its name and final texture. It would resemble a massive netherite golem, larger than a Warden, with eyes, a nose, a mouth, huge arms, legs and chest. It would have no baby form.

Proposed stats: 1,800 health points (900 hearts), movement speed 0.7 and melee damage of 138 points. Striking netherrack or other Nether ground would summon netherite spikes. It would throw heavy cores and dangerous wither skulls. Deep growls would shake the first-person camera.

It would attack players, piglins, hoglins and baby turtles, but would not deliberately target zombified piglins or zoglins. Zoglins could retaliate if attacked.

A roar would deal 19 damage: an unprotected full-health player would have 1 health point left, a regular piglin would die, a piglin brute would have 31 health points left, and a hoglin would have 21 health points left.

The goal is an intense late-game Nether challenge. These numbers are proposals; clear attack warnings and ways to dodge would make the fight possible in Survival. If necessary, players using commands could remove it with /kill. Then, add a spawn egg of that evil beast.