One Enchanted card is found approximately once every 100 booster packs, or every 1,200 cards
Better yet, steal a blocker from someone else, chump with it, then untap Shackles and do it again the following turn
Likewise, it usually would have to attack to die and trigger its ability or be sacrificed to an ability to get the token and start a loop
Note that Planar Nexus counts as a town now (in all zones), and the everything counter from Omo, Queen of Vesuva adds the town subtype to the land it modifies
But when used on a creature you control, you get to unlock its true potential
If you have no use for mana, you can use the -2 ability to Anticipate and search for necessary cards