Eltaclev, Corrupt Virtuoso

If Eltaclev, Corrupt Virtuoso is your
commander, your deck can have any number of
cards named Crawling Chorus.
Whenever another creature enters the battlefield
under your control, look at the top card of your
library. If it's a creature card with converted
mana cost 1 or less, you may reveal it and put it
into your hand. If you don't put the card into
your hand, you may put it on the bottom of
your library.