Withering Wisps's triggered ability has an "intervening 'if' clause." That means (1) the ability won't trigger at all unless there are no creatures on the battlefield when a turn's end step begins, and (2) the ability will do nothing if there are any creatures on the battlefield by the time the ability resolves.
2008-10-01
wotc
The number of snow Swamps you control and the number of times Withering Wisps's ability has been activated so far that turn are checked each time you attempt to activate the ability.
2008-10-01
wotc
If all creatures leave the battlefield during a turn's End step (after any "at the beginning of the end step" triggers would have triggered that turn), Withering Wisps will remain on the battlefield because the trigger condition has already passed.
Format Legality
Standard
Not Legal
Future
Not Legal
Historic
Not Legal
Timeless
Not Legal
Gladiator
Not Legal
Pioneer
Not Legal
Modern
Not Legal
Legacy
Legal
Pauper
Not Legal
Vintage
Legal
Penny
Not Legal
Commander
Legal
Oathbreaker
Legal
Standardbrawl
Not Legal
Brawl
Not Legal
Alchemy
Not Legal
Paupercommander
Not Legal
Duel
Legal
Oldschool
Not Legal
Premodern
Legal
Predh
Legal
Who's Online
Live site activity across collectors, guests, and crawlers.