Arixmethes, submerged

Arixmethes submerged enters the battlefield with seven slumber counters on it
as long as Arixmethes submerged has a slumber counter on it it is a landwhenever you play a card with {u} in its mana cost
remove a slumber from Arixmethes submerged
{t} add {u}{u} to your mana pool