WotC_BenFinkel

Yes, assuming you use The Chain Veil's permission last (which Arena enables easily). #wotc_staff

I too was confused, but it is consistent with other effects in the game like "Creatures your opponents control can't block this turn." That also doesn't care about the state of objects as that ability resolves, but rather what is around when the opponents try to block. I do think the "for each" wording adds to the confusion here, but admittedly the desired effect is hard to word. #wotc_staff

Could be reasonable. A complication is that the activations count even before The Chain Veil enters the battlefield. And added to that, we prefer not to load the code for abilities that aren't currently in the game - if you were to get The Chain Veil from some sort of conjuration effect, we want those old activations to count even if The Chain Veil's code wasn't in the game at time of activation. #wotc_staff

By my understanding of MTG's usage of "as though", The Chain Veil wouldn't interact interestingly with that. The Chain Veil just affects whether you're permitted to activate the ability, not whether that activation actually counts as the first time it was activated this turn. Similar weirdness exists around "as though it were mana of any color." #wotc_staff

Hello reddit! [[The Chain Veil]] was the most interesting Pioneer Masters card I worked on implementing for MTG Arena, so I'm happy to preview it for you.

Both of the abilities involved some new-to-Arena mechanics. The triggered ability involved me teaching our "activate" verb handling about how to behave in a condition phrase - here, to look throughout the history of ability activations for this turn for a loyalty ability's activation whose source was, at the time of activation, a planeswalker. Lots of testing around this for "what about other abilities on planeswalkers?" "What about permanents that weren't planeswalkers but had loyalty abilities, but are planeswalkers now that it's the end step?" And many more in that ilk.

The activated ability is certainly the more fun one. But it's interestingly very different from similar extra-activation abilities like [[Oath of Teferi]] and [[Urza, Planeswalker]]. In particular, each activation of The Chain Veil gives a speci...

Thanks for the report, I'll look into it. EDIT: The gist of the bug is that Valiant Emberkin is retriggering each of the triggered abilities for each creature you control that the source spell/ability targets, instead of once. Here is an article my colleague Alex wrote about our card ability code that illustrates a bit of why this bug happens. Working on a fix now! #wotc_staff

This bug made me lose (there was no bug)

It's this sort of thing that really makes my day! (And makes it hurt when there really is a bug, as if it didn't already!). #wotc_staff

I'd like to give a shoutout to Underworld Breach. It had two classes of major problems due to being the first card to confer a non-mana cost to arbitrary cards.

Firstly, it made payment and affordability checks much more complicated. If you have something like Tormenting Voice, you can discard a card for the additional cost before exiling it from your graveyard. We don't let you choose payment order on Arena, so we had to change things to get the order to be smart here. For affordability, we had to predict how the costs could interact in terms of payment resources.

The other major category was linked ability bugs. Cards exiled to pay the escape cost were incorrectly linking to text like "the exiled card" due to us not yet having a good signal that the escape cost wasn't "native" to the card. We played whack-a-mole with bugs in this space for months before getting a more general solution that seems to work for all current MTG behavior (fingers crossed!). #wotc_staff...

The issue there was that the Evoke action was incorrectly taking credit both for being an alternative cost (correct) AND for being the permission source of the action (wrong, Muldrotha is). So when deciding whether to use up part of Muldrotha's permission, the action isn't marked as relevant. The fix was a one line change to have the Evoke action copy over the permission source from the action it was duplicating instead of overwriting it. Definitely the sort of typical human error Alex alludes to. #wotc_staff

Unknown Shores (and mana filtering in general) is kind of a pain in the butt for Autotap too, so having it in RoboQA games helps stress test Autotap's performance and internal assertions about its correctness too. #wotc_staff

This feature actually does exist. What you need to do is use the View Battlefield option at the end of the game, then mouse over the facedown cards you want to look at. #wotc_staff

Thank you for the report (and thanks /u/Judge_Todd for the ping). The nature of this bug is that while investigate is set up to create the token under your ownership and control, and it does count as a token being created, you aren't credited as being the one who created it, so Mirkwood Bat's "Whenever you create..." isn't triggering. We'll get the fix out as soon as possible. #wotc_staff

Can you clarify? I believe this was fixed in the SOI Remastered release as I said. Are there still scenarios where it is failing to transform properly? #wotc_staff

Arguably the whole concept of "parsing cards" is AI. As are AutoTap and the system that navigates a player to the end of their turn if they run out of time (AutoResponder). And additionally we have a system called RoboQA that nightly plays hundreds of thousands of games against itself looking for ways to crash the game (it's the world's most experienced MTG player!).

After all, AI is a pretty wide term - it's "an artificial system that does stuff that are associated with intelligence". Still, all of our systems are as deterministic as possible - we don't leverage big data or probability distributions or randomization as a matter of course. Well, RoboQA does. #wotc_staff

Parse-wise, the bug here is that this is the first time I'm aware of for Arena where the dependency exists because of some "distant" clause in the rules text - the parser didn't see the contents of the "as long as" clause when considering what may be relevant for dependencies for the "Grond, the Gatebreaker is an artifact creature" phrase. The sorts of dependencies we've handled in the past are those like [[Ashaya, Soul of the Wild]], where the "required" types (Nontoken creatures you control) are in the same phrase as the "dependent" types (Forest lands).

We hope to get the fix out for this dependency issue soon. #wotc_staff

Have you checked it this week? The fix was released with Shadows over Innistrad: Remastered. It took so long because the development team wasn't aware of it until somewhat recently; we're working on improving the user bug report pipeline. #wotc_staff

Thanks. Our team is looking into it. #wotc_staff

The post has been deleted. Can you share what it was? #wotc_staff

A syntax error due to being unfamiliar with the phrase "After that turn". #wotc_staff