“ Chekov's Spell -- This spell has a two-fold effect. The first is to make the target item almost-unnoticeable to anyone not specifically looking for it. The second is that someone who has seen the item will remember it when they encounter a situation that would be perfectly solved by use of said item.”
“ 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.”
“ At regular intervals, a god takes control of your world's weather. Choose the gods at random each turn of the interval and begin applying their effects subtly. Their power will depend on the strength of those who worship them.
For civilised people, worship of a god actually wanes during that god's month in an effort to reduce their potential destructive effect.”