Severn the Watcher

This spell cannot be countered.
Deathtouch, first strike, hexproof
When Severn the Watcher enters the battlefield,
look at the top and bottom three cards of your
library. Put any number of them in any order on
the top of your library and put the rest in any
order on the bottom of your library.
{u/b}{u/b}{t}: Scry 4, draw 1
{u/b}{u/b}{r}{u}: Severn the Watcher gains unblockable
until end of turn.