Susie's Epic Adventure/2 Make the poison

You decide to get the cadava berries first. You south of Varrock and see a large stone circle with a bunch of dark wizards in it. One of them talks to you.

"Hey, are you Susie?"

"Yes." You say

"The powerful Zamorakian mage, Susie?"

"Are there any other Susies?"

"Good. You see here, we're trying to summon the great demon, Delrith. It would mean a lot to us if you helped."

"Golly, Gee. I would love to cause great destruction for the great lord Zamorak, but I really have to get this cake ready..." But then you stop to think- Causing great destruction for Zammy would make him really happy. But what if you're just wasting your time summoning this demon? What do you do?

Well...

 * 1) Destroy Varrock
 * 2) Make poisonous cake