“ Believable magic, like ordinary physicis, operates according to some invariable laws that always result in some kind of cost or 'bounce back'. The grater the magic, the more it should cost the character physically, emotionally, and spiritually.”
“ Gnomes are famous for their festive springtime celebrations. Farm villages will often dye their hens eggs bright colors; with gnomish magic, the chicks that hatch from the eggs have the very same colors. The chickens eventually lose their hues, but the stronger the magic, the longer the color stays. In a gnomish village, one can easily spot the village shaman by his flock of gaily colored fowl.”
“ A continent is home to large, leathery flying beasts with a wingspan of over 70ft. Though shy, herbivorous and easily scared, it is possible that an enterprising person could domesticate them. They would be useless in war due to their timidity, but excellent if used for commercial air travel.”