Once and Future King

Exalted (Whenever a creature you control attacks
alone, that creature gets +1/+1 until end of turn.)
Basic Lands you control have Exalted (If a
creature has multiple instances of exalted, each
triggers separately.)
Whenever a creature you control attacks alone,
search your library for a basic land card, reveal it,
put it onto the battlefield, then shuffle your
library.