Oracle

Enchantment 

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

NederMagic FAQ

Vraag: Hoe werkt dit met Planeswalkers en hun loyalty counters?
Antwoord: Planeswalkers komen met het dubbele aantal loyalty counters in het spel; inderdaad, dat betekent meestal dat je meteen hun "ultimate" kunt gebruiken! Het betalen van de cost (loyalty counters erop of eraf) wordt namelijk niet verdubbeld.

Vraag: Vraag: is hier een kaart van de dag voor geschreven?

Antwoord: ja hier !

Tournooi-info

Legal in: Vintage, Legacy, Modern, Commander

Officiele rulings

8/7/2020
Doubling Season affects permanents that enter the battlefield with a certain number of counters.

8/7/2020
Planeswalkers will enter the battlefield with double the normal number of loyalty counters. However, if you activate an ability whose cost has you put loyalty counters on a planeswalker, the number you put on isn’t doubled. This is because those counters are put on as a cost, not as an effect.

8/7/2020
If there are two Doubling Seasons on the battlefield, then the number of tokens or counters is four times the original number. If there are three on the battlefield, then the number of tokens or counters is eight times the original number, and so on.

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