Do timed spell effects in Riftbound apply continuously to everything during their duration, or do they only apply to things present at resolution (snapshot)?

Ruling: Spell effects snapshot at resolution and only apply to things that are present when the spell resolves, not to things that enter play later during the effect's duration.

Nuances:

• This applies similarly to cards like Stand United, which would only increase the might of buffs that were in play when Stand United's text was executed
• While this ruling is confirmed by official Red Text, it is not explicitly detailed in the Comprehensive Rules Document