For Grand Plaza, when is the '7+ units' condition checked - when deciding whether the ability triggers and enters the chain, or after it's already on the chain during resolution?

Ruling: The '7+ units' condition is checked at the moment you hold the battlefield to determine whether the ability triggers and is placed on the chain at all. If you have fewer than 7 units when you hold, the ability does not trigger.

Sequence:

• During your Beginning Phase, you hold the battlefield
• The game immediately checks if you have 7+ units at that battlefield
• If you have 7+ units: the ability is placed on the chain as a Pending Item
• If you have fewer than 7 units: the ability does not trigger or go on the chain

Nuances:

• The '7+ units' requirement acts as a gatekeeper - it must be true for the ability to enter the chain
• You cannot use the priority window after the ability triggers to add more units to meet the requirement, because the ability only triggers if you already have 7+ units
• This is because conditional statements following a trigger condition must be true for the trigger to be placed on the chain