Flash
When Portal Mage enters during the declare attackers step, you may reselect which player or permanent target attacking creature is attacking. (It can’t attack its controller or their permanents.)
If an ability targets something controlled by the “defending player” of an attacking creature and the defending player for that creature changes before that ability resolves, the ability won’t resolve because its target has become illegal.
25-08-2017
wotc
You may cast Portal Mage outside of a declare attackers step. If Portal Mage enters the battlefield outside of a declare attackers step, its ability simply doesn’t trigger.
25-08-2017
wotc
Reselecting which player or planeswalker a creature is attacking ignores all requirements, restrictions, and costs associated with attacking.
25-08-2017
wotc
Reselecting which player or planeswalker a creature is attacking doesn’t cause “whenever this creature attacks” abilities to trigger. Notably, the Curses in this set (such as Curse of Vitality) won’t trigger while Portal Mage’s ability is resolving.
25-08-2017
wotc
If you reselect which player or planeswalker an attacking creature is attacking, that creature is still considered to have attacked the player or planeswalker as declared, but it is now attacking the new player or planeswalker.
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.