The streamer Dane recently made a video about a seemingly bugged interaction between Magic carpet and Anka. I investigated a bit, and came up with this. Wrote it in a comment, I’ll repost it below:
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Oh wow, sorry I totally missed the card text of Anka. It looks bugged alright. Anyway, let’s look at what the cards actually say.
Luna’s says: “Change the cost of minions in your deck to (1)”. Does not mention reduction in it’s card text, minions work with carpet.
Summoning Portal says: “Your minions cost (2) less, but not less than (1).” Does not mention reduction in it’s card text, minions affected by this aura work with carpet.
Sea Giant says: “Costs (1) less for each other minion on the battlefield.” Does not mention reduction in it’s card text, works with carpet.
Mechwarper says: “Your Mechs cost (1) less.” Does not mention reduction in it’s card text, functions the same as portal.
Thaurissan says: “At the end of your turn, reduce the Cost of cards in your hand by (1).” Mentions reduction, reduced minions do NOT work with carpet.
Galvanizer says: “Battlecry: Reduce the Cost of Mechs in your hand by (1).” Mentions reduction, reduced minions do NOT work with carpet.
Could probably go on, but you get the point. The game does not include cost-“reduced” cards when it looks for 1-cost cards, only original 1-drops (like mecharoo), cost-“changed” cards (like Luna’s), cards with costs affected by passive auras (like portal, Giant works much the same), or copies created to cost 1(like those of sonyas). However, the wording of Anka is the same that Luna’s have: “Change”.
Anka’s card text says: Battlecry: “Change each Deathrattle minion in your hand into a 1/1 that costs (1).”
It’s the only one I know of that breaks this pattern. So yeah, fair to say it’s bugged.
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Am I wrong about this stuff? Anka seems inconsistent. It’s very late, sorry if I’ve been unclear.
Yes, it’s a bug. It’s believed to have emerged as a side effect of “fixing” the bugged interaction between Duel and Freezing Trap. When a minion enters the battlefield, cost modifiers are removed. However, it seems that removal used to be done with a weirdly late timing, where a minion that was summoned by Duel but returned by Freezing Trap would get the cost increase removed as a consequence of its prior summoning.
This seems to have been fixed by changing a bunch of cost enchantments to remove at an earlier time, but this has caused them to no longer be recognized by Magic Carpet.
Some other cases are documented here:
https://github.com/HearthSim/hs-bugs/issues/1182
Interestingly, a test a while back indicated that Thaurissan and Galvanizer’s reductions were recognized by Magic Carpet. Did you test this recently?
No, I found some posts regarding Magic Carpet, pre Anka release. I just cobbled together what I could find from other who had tested it, I’m unaware of what patches have been made since the release of Carpet. I guess it’s been inconsistent all along then. This is really bugging me.
Someone told me skulking geist can remove spells that have had their cost reduced by Thaurissan, however the hs wiki says it does not work with Apprentice cost reduction. The game is just a hot mess.
What I want is to understand is if “reduced” and “changed” work differently, and why, wheather Carpet and Geist are supposed to trigger differently for enchanted cards, aura-affected cards, copied card and original 1-drops. If 1-cost card refers to cards with a base cost of 1 (unenchanted or copies), why do ‘costs x’-auras work with Carpet? And is Luna’s and Anka supposed to work?
Geist is uniquely intended to work entirely from base cost. It’s a relatively safe assumption that Magic Carpet is supposed to work by the cost of the minion when played, including modifications, and that the difference between adjustment and setter effects should not matter. No official statement has been made, but Sonya and Shadowcaster were updated semi-recently to once again have their copies buffed by Carpet.