Yes!!! I have done it I killed the toadstool, SOLO!
I was able to get him stuck on a pond (See this thread about more information:)
I made a couple of Night Swords and found the pan flute near Glommer a few days before. (I also had 5 spears which I wasted 'em all on him)
When he tried to go back to his hole to spawn those sporecaps I was able to kill him easily with my minions and my 2 rockys
I feel a bit bad I used this method to kill him, but I think it was worth it. I know most of you will disagree with my plan...
I did die once with the mushrooms but I found a touch stone in the caves and I got ressurected, the second try I got to kill him!
I did have a mod that make my minions' kite be disabled... so they just kept hitting him.
I am proud to say I defeated him using NO console!