Tamashi, Excellent Assistant

When Tamashi enters the battlefield, select target opponent. At the start of that player's upkeep,
you may untap all permanents you control and
draw a card. You may cast creature, enchantment,
artifact and sorcery spells during that player's
main phases as if they had flash. If you do, that
player gains control of that spell. Creatures
you control may block creatures attacking that
player.
Tamashi gains +1/+1 for each permanent you
own under an opponent's control.