Now my idea’s are to make these things quickly without much trouble so above can be done a few ways.

You can get either premade cupcakes and put them on the plate or a chocolate coated  biscuit like say a mint slice.

Use chocolate covered pocky as the legs or chocolate sryup to do the design on the plate and you have spiders :)

Also if you have some white chocolate you can quickly melt then get some chocolate biscuits and do a design ontop of it like a skull, spider web etc.