Greater Mindscape Question: Believable Creatures

[TheYell]

Looking ahead to ask a rules question: Does creating an illusory, believable creature in a mindscape allow me to attack my target with monsters?

[TheYell]

Perhaps I'm too terse.

My drow-changeling has a clear memory of the old homestead's slave combat arena (I figure any society with slaves has at least one guy who made them fight for amusement). So her greater mindscape will be an unlit arena with a dozen giant spiders ready to attack the target while she lounges in the owner's box on a throne having a cold one.

RAW I can have a number of believable creatures animated in my mindscape to interact with the target. RAW this doesn't specifically include combat. I'm trying to see if people think that combat is within the realm of RAI possibility? Maybe its a question of degree, because I can see a dozen hostile mindless vermin being on a totally different scale than "You are surrounded by a dozen hostile elder red dragons, cause I imagine it." Not that the text sets any such limits, but then it doesn't specifically open the door to combat either.


Is it just a question of what the DM agrees with?