“ Magic is like alcohol, the more that is used, the more it causes a hangover later on and the less judgement one has when using it. If one waits a while after casting a spell, things 'detoxify.' A cantrip or two is like a sip of weak beer, whilst a large creation spell is like a bottle of vodka. Cast something too big and you can die from magic intoxication.”
“ Whilst exploring underground the PCs discover tube like tunnels stretching for miles, upon further inspection the strange tunnels seem to connect all major cities in the are, what is their purpose?”