They are all rare, but there are several guaranteed of each. For example, the spider silk carries cloning & SOCM I believe. Then just hoard them instead of using them early. Once you get 4 or 5, even if you only have 1 wand of cloning with 2 charges, you will get 15 just like that (*snap*)
Thanks. In my previous experience, Oree himself is pretty easy, but the mage rooms will be tough. And once I beat Oree I will want to kill Petrus, that will be hard too