Sword of Light and Shadow can help you get a creature back from the graveyard to keep using it if one ever does get removed
For example, if Strata Scythe's imprint ability ("When this Equipment enters, search your library for a land card, exile it, then shuffle.") triggers twice (probably because it somehow entered attached to Cloud), up to two total land cards can be exiled
It also doesn't hurt that she plays so well with the lands you can easily fit in a Mono-White deck in Fountainport, Mirrex, and the new land Dalkovan Encampment
Playing them early makes them hard to remove and will almost always give you benefits
This guy was built for Commander despite his only printing coming well before the formats popularity and his asking price is still under $10
If you dont know, beginning in 1999 you had a small chance of any regular card in your MTG booster pack being replaced with a shiny foil version of that card instead