Titania, Protector of Argoth is another great reprint story
If you have six or more, it won't trigger at all
Along with being intimidating, most players don't have the time or budget to try out a bunch of different decks
Pushing the impactful cards to higher rarities helps make the games more even-keeled in Limited because of card as-fans (the rate at which a certain card or subset of cards show up within an average booster pack) and in casual Constructed because of card availability
As a land, it loses all other card types and abilities, effectively locking it out of the game so long as the enchantment remains in play
The deck eschews the pillow fort strategy that enchantment decks sometimes do (no Ghostly Prison or the like here), or the combo draw everything approach including lots of 1 mana enchantments for a tap out control style of play, with extra value coming from your enchantment synergies