Can I make slanted wedges for a tilted tiered cake out of carved rice crispy treats instead? Can it support the weight if it's dowelled and with own cake circles like a styro dummy? I have to make a 3 tiered cake for a charity event. The design is a'la' collette peters design. If I dowel each tier and then a single dowel through whole cake and wedges. Will this work or do I need styrofoam or dummy cakes carved?

I dunno - don't have a huge amount of experience with this type of cake, but I'd be a little nervous that even the most rigid of rice cereal treat layers might not hold up. I'd go with the styrofoam layers myself!

I would just do the foam wedges,1 foam round will give you 2 wedges, which is all you need for a 3 tier cake.