Can Stealth bot take the damage Legacy does himself as part of Heroic Interception and be immune to it, or is no one immune untill after the damge has been dealt?
Yes, the damage could be redirected to Stealth bot who be immune at that point.
Heroic Interception deals the damage to Legacy first. Other hero targets are made immune second, after the damage is resolved. So no, you can not get around the damage to Legacy by redirecting it.
Not true. The effect of Heroic Interception takes place immediately upon coming into play and damage redirected to Stealth Bot would result in no damage.
How do you know this to be the case? This is very far removed from how my understanding of card effects similar to this work. I'll have to go home and look at the card to see how it's worded.
The card reads:
When this card enters play, Legacy deals himself 3 Melee Damage.
Hero Targets other than Legacy are immune to Damage.
At the start of your turn, destroy this card.
There is no "and then" or order of operations. The effect is not conditional on the damage. The text on an ongoing card means when that card is in play, that text applies.
As soon as the card is in play, the immunity takes effect. Stealth Bot is immune, and can tank the damage for Legacy. I've done it in the app a couple times.
I was incorrect about the card. In my head, the card text was "When this card is played..." rather than "When this card enters play...".
I don't think that would have made any difference at all in regards to the Stealth Bot example.
Playing a card necessarily precedes the effect of that card. If the card's damage triggered on being played, that would resolve before the immunity effect of the card.
[quote=“Fireside Chats”]
When a card enters play, the following order of things occurs.
- Ongoing effects on the card become applicable.
- Cards that react to other cards entering play now act.
- One-time effects on the card happen.
A well-known example of this is Informant. Suppose Informant and Combat Stance are in play and Legacy plays Inspiring Presence.
- Damage dealt by hero targets is now increased by 1.
- Informant causes The Chairman to play a card. Suppose it’s Undivided Attention, damaging The Wraith. Combat Stance reacts and its damage is increased by 1 due to Inspiring Presence.
- All hero targets regain 1 HP.
Another example: Supercooled Trisolvent Vat and Synaptic Interruption. Suppose damage dealt to Tachyon is increased by 2. When Tachyon plays Synaptic Interruption, the Vat does 3 cold damage to Tachyon. Tachyon may redirect the damage and destroy Synaptic Interruption.
[/quote]
The Informant's game text is "When a Hero card is played, play the top card of the villain deck.".
Did "enters play" become interchangeable with "played"?
https://greaterthangames.com/comment/59875#comment-59875
My understanding is that played triggers happen before a card enters play, or any enters-play triggers.
It doesn't much matter in this case I don't think. Either way, the ongoing immunity clause of the card still is in effect. There is no language on the card that says the ongoing effect must happen afer some other effect, and the order of effects listed on the card is not enough in and of itself to suggest that it is (see Ra's Imbued Fire).
I don't think there is a difference in timing between "played" and "enters play".
For example, if Positive Energy Field ("Whenever a card is played") and Mask of the Matriach ("when a non-fowl card enters play") are both out, you can choose which triggers first.
That being said, none of this applies to destroying the Informant, as there is a separate issue there. "Played" or "enters play" triggers of other cards will always trigger before a "enters play" trigger of the card being played (or entering play). This is why a new card can't stop the Informant from triggering.
'Enters play' is (and always was) interchangeable with 'played'. 'Played' triggers (like in the referenced comment) happen after the card has entered play, but before it's text begins to resolve, as described in the comment you linked to, and as described by the fireside chats. Except that static effects (like Heroic interception's damage immunity) don't resolve at all, they're just 'on' all the time that the card is in play.
Am I correct in guessing that you play Magic? In MtG, 'enters play' and 'played' are seperate because of the existence of the stack. But SotM doesn't have a stack, so it combines the two, and SotM's language hasn't been completely standardized yet, thus occasionally using two terms for the same thing.
I have seen this statement made many times, and I can't agree with it. It may not acknowledge the existence of a stack anywhere in the rules (or offical rulings), but it certainly behaves like a stack. I've been playing a lot in the app lately with a combination of Argent Adept and Grandpa Legacy handing powers back and forth to each other, and I'm certainly glad that the app can keep track of all the nested state (i.e. stack) that's involved there. If it looks like a duck and it quacks like a duck…
I don't deny that there are significant differences between MtG and SotM, but "having a stack" is not one of them.
Maybe it does have a stack, but not the same way MtG does. In Magic, the stack is discrete on the ability level (entire abilities resolve before the game state reacts to the changes) and there is time to respond between the triggering of abilties and their resolution. In SotM, the 'stack' is discrete on an action level, and abilties resolve as soon as they are triggered. The second one matters less (since SotM doesn't have 'instant speed' actions (yet)), but these differences make the SotM system sufficiently distinct from Magic's stack that trying to understand SotM timing using Magic's stack will frequently provide the wrong answer, which is why we try to discourage people from saying that SotM has a stack. Maybe it does, but the comparison is rarely helpful.
In this particular instance, the point I was trying to make was that spells in Magic need to distinct terms for 'playing' and 'entering play' because they use the stack to enter a limbo of 'will happen, but first giving you a chance to respond' that SotM doesn't have. In SotM, the moment that you play a card it starts happening.
Text that is a static effect, like Heroic Interception's immunity or Inspiring Pesence don't activate or de-activate.
If the card is in play the effect is active. If the card is not in play the effect is not active.
For eexample if The Informant is in play and Legacy plays Takedown no card will be played by the Informant's effect, because "Villain cards cannot be played" is a static effect, and the card is in play, so it is in effect.
Mistbound cannot stop the card play because the response happens before the text on Mistbound resolves. Text on one-shots is resolved after the card enters play, by rule, and since the card play prevention is not a static effect it is not active when Informant responds to Mistbound entering play.
Thank you for the patient and elucidating reply!
I guess my objection is because I first had the term "stack" enter my brain about 30 years ago in a Computer Science class, and both MtG and SotM clearly (to me) follow that concept 
I agree with you there. You might say (although I don't recommend it) that SotM uses a stack, but doesn't use The Stack.
Double agree! I was also confused by people saying that Sentinels didn’t have a stack, because I’m familiar with computational data structures but not with Magic. Now I know!