How does the updated Rule 506.3 work regarding when players must announce triggers, specifically what counts as an 'observable impact on the game'?

Ruling: Players must announce triggers when they have an observable impact on the game, meaning any known change to the board state or zone contents. Triggers that only create temporary stat changes (like buffs) don't need to be called out immediately but are assumed to be remembered until you demonstrate you've missed them.

Sequence:

• Triggers with immediate observable impact (gaining points, exhausting runes, drawing cards) must be announced when they occur
• Triggers that only create temporary stat changes (like Ravenbloom Student's +1 or Thousand-Tailed Watcher's minuses) don't need immediate announcement
• These stat change triggers are assumed remembered until you take an action that demonstrates you forgot them
• Once more than a turn cycle has passed, missed triggers cannot be retroactively applied

Nuances:

• The Arena's Greatest giving points must be called out immediately as it's an observable impact
• Obelisk of Power's rune channeling must be announced as it observably impacts the game
• If you have a buffed unit (like Ravenbloom at +2) and take an action inconsistent with remembering the buff (like putting it in trash during combat when it should have survived), you've demonstrated you missed the trigger
• You should still call out stat change triggers as best practice, but you're not assumed to have missed them just for not announcing immediately