Whenever you cast your first instant or sorcery spell each turn, exile an instant or sorcery card at random from your graveyard. Then copy each card exiled with Arcane Bombardment. You may cast any number of the copies without paying their mana costs.
If you cast a spell with {X} in its cost without paying its mana cost, you must choose 0 for X.
29-04-2022
wotc
The spell that caused Arcane Bombardment's ability to trigger is normally still on the stack while that ability resolves. That spell won't be among the cards in your graveyard when you exile an instant or sorcery from it at random.
29-04-2022
wotc
If you've already cast an instant or sorcery spell the turn that Arcane Bombardment enters the battlefield, it won't trigger until you cast an instant or sorcery spell on a later turn.
29-04-2022
wotc
If Arcane Bombardment leaves the battlefield, the exiled cards remain in exile. If it returns to the battlefield or you play another copy of it, you won't get to cast copies of the cards previously exiled.
29-04-2022
wotc
You cast the desired copies as the triggered ability resolves. You don't get to cast them later in the turn. You choose the order of copies as you cast them.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.