Between this, Restoration Magic and Moogles' Valor, white has several ways to really punish you for attacking into open mana
This set comes from the original Commander preconstructed decks from 2011 which is around 13 years old at this point, making it much less likely anyone will have an unopened version of this deck lying around, much less one in a good condition.
That may not seem like much but if the opponent is unable to take Calhoun out in one strike, that resist +1 may effectively double her health
When playing Voltron, its often one or two permanents that tend to provide the big hurdles, and having repeatable removal is incredible
Shalai and Hallar Shalai and Hallar is one of the strongest team-up cards from March of the Machine
For example, if Narod, the Beige Flower and Doran, the Siege Tower ("Each creature assigns combat damage equal to its toughness rather than its power") are both on the battlefield, each time a creature would deal combat damage, that creature's controller chooses whether it assigns combat damage equal to its mana value or its toughness
