The broader target range and better late game scaling make Oust the better control card but both are good enough that you will play either in either if you just need more removal
You must follow the normal timing permissions and restrictions of the spell you cast from among those cards
Rather than using any fancy tricks, this deck is all about sheer overwhelming infectious might
Activated abilities include a colon and are written in the form "[cost]: [effect]." No one can activate any activated abilities, including mana abilities, of a detained permanent
I played this card, by the way, at the draft we played when the cards first came in (yes, we get excited when we get the cards too it just happens earlier for us) and it was a beating
In addition to taxing each of your opponents' spells by one mana, slowing them down significantly, Grand Arbiter Augustin IV provides you with a significant mana discount on your blue and white spells, respectively, providing an even greater cost reduction to Azorius spells