Polaris Coach and Heidelberg Castle

Amin wrote:

Thank you

I think I get it now (correct me if I'm wrong): it triggers once during the untap phase and the controller chooses when exactly. It is different to the lasting effects like Recalled to the Founder or Anarch Revolt (www.vekn.net/index.php/forum/6-rules-questions/44217-recalled-to-the-founder) which are checking the conditions all the time during the untap phase. Right?

No, it's exactly the same. You can trigger it anytime as long as you meet the condition (if any). You can't trigger it if you don't meet the conditions.

For instance, you can choose to apply Recalled to the Founder and burn a vampire after using a Vessel.
But if you start the untap phase without meeting RttF's criteria (controlling more than 2 vampires of the same clan), you can't apply it THEN put another vampire into play (say a Web of Knife Recruit) in order to skip RttF effect.

As LSJ explained (about Anarch Revolt):

Xe has to control at least one ready anarch at the end of xer untap phase to
avoid losing pool.
The effect cannot be applied if the player has any ready anarchs. And the player cannot leave xer untap phase without handling the effect if xe has no ready
anarchs. The combination of those two points leads to my first sentence above.

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