T
train
Guest
you put a squirrel nest on a land... any land... preferably one that turns into a creature when you pay an activation cost, but any will work as long as you animate it into a creature...
with an intruder alarm in play... use other lands to activate the "man-land" turning it into a creature, tap it to put a squirrel into play, then it untaps when the squirrel comes into play (intruder alarm) and you do this as many times as you want...
similarly, with mana producing elves - you make more squirrels, tapping elves for mana each turn, then untapping them and generating more and more mana...
there's also the enduring renewal, 0CC creature, and ashnod's altar comb... Enduring renewal returns a creature to your hand when it goes to the gy from play... with the altar out, sac the 0cc creature for mana, play it for free (it's back in hand now) and was rinse, repeat...
those are just a few...
with an intruder alarm in play... use other lands to activate the "man-land" turning it into a creature, tap it to put a squirrel into play, then it untaps when the squirrel comes into play (intruder alarm) and you do this as many times as you want...
similarly, with mana producing elves - you make more squirrels, tapping elves for mana each turn, then untapping them and generating more and more mana...
there's also the enduring renewal, 0CC creature, and ashnod's altar comb... Enduring renewal returns a creature to your hand when it goes to the gy from play... with the altar out, sac the 0cc creature for mana, play it for free (it's back in hand now) and was rinse, repeat...
those are just a few...