Lydrom, Great Mage Ring

When Lydrom, Great Mage Ring enters the battlefield, return up to 4 basic lands from the battlefield to your hand.
{t}: Add {x} amount of mana in any combination
of {u} and/or {g}, where {x} is the number of
lands you returned to your hand.
{6}: Put all basic and non-basic land cards
from your hand onto the battlefield untapped.