Cosmic Memento

at the start of your opponents turn you may reveal the top card of your opponents library if it is a land he/she plays it tapped if it is anything other then a land they draw it
{t}you may place the top card of your opponents to the bottom of their library the next card drawn costs 2 less to play
the phoenix's egg was used to power this device and this device gives me knowledge of worlds beyond this one but at what cost