Infinitely respawning monster

Not sure if this works in Vanilla doom or Any old scripts besides ACS

you can achieve this by Loops 

https://zdoom.org/wiki/Loops

Chubbzdoomer has a Tutorial video on loops if you want to see how its done

ill take a look at that Maisth, thanks!

You can do this in DECORATE by giving the monster the ALWAYSRESPAWN flag.

actor Fatso2 : Fatso 1067
{
  +ALWAYSRESPAWN
}

This makes a new monster that inherits from the mancubus (called Fatso here), gives the new monster a DoomEd number (1067, the default mancubus number + 1000), and adds the flag to it. Use Slade to put this code in the DECORATE lump in your wad, and place thing number 1067 in your map wherever you want the respawning mancubus.

Thank you Empyre! Thats really awesome!