an more complicated alchemy system, not the to obvious red flowers, blue flowers... but every plant has some chemical properties. The player would then need 1 to find books with detailed recepies for potions or he could just guess about and kill himself in a explosion caused by a chemical reaction <img src="/ubbthreads/images/graemlins/tongue.gif" alt="" /> Most recepies should be spread over the world in scrolls, books etc. Some aren't written down and can just be found out by coincidence. Some plants just don't do a thing but are still able to be extracted. All strong potios should include dangers on making them. not a chance thing but things as wrong amounts = wrong effect, even deadly.
Should be fun and frustrating at some point <img src="/ubbthreads/images/graemlins/tongue.gif" alt="" />