Brutal Nightmare : Insane Difficult

Fix and rebalance the spawn mechanic, +3 new modifiers

• Fix spawn bug

• Fix Skeleton AI bug. Also, zombie & husk place dirt instead of stone

• Fix Settings bug (Thank DatTango)

• Fix bugs (Thanks DatTango for reporting)

• Fix bugs (Thank DatTango for reporting)

• Quick fix

• Support 1.21.5, rebuild with Relix 7
• Update more modifiers, change the menu.