Do 'As I'm revealed' effects (like on Undertitan and Nocturne) interrupt the current action to resolve immediately, or do they get added to the chain afterwards?

Ruling: 'As I'm revealed' effects resolve immediately when the card is revealed. They do not go on the chain or create triggers.

Sequence:

• Card is revealed
• 'As' effect happens immediately (interrupting the current action)
• Continue with the action that caused the reveal

Nuances:

• These are not templated as reactions or triggers
• Add abilities in general do not go on the stack and resolve straight away
• Reaction add effects do go on the chain but don't create opportunity for either player (this is different from 'as' effects)
• The FAQ for Nocturne confirms this immediate resolution timing
• There is no explicit comprehensive rule document for this interaction yet, but the absence of rules saying these effects trigger or go on the chain means they resolve immediately as written