Ratatoskr, The Sly Messenger

Indestructible
When Ratatoskr, The Sly Messenger enters the battlefield, tap all creatures your opponents
control
{2}{u}{r}{g}: Choose two target creatures, shuffle
them into their owner's libraries. Their
owners then reveal cards from the top of their
library until they reveal a creature. Put them onto
the battlefield, those two creatures fight. All other
cards revealed this way are put to the bottom of
their owner's library