Per Saffron Olive's Tweet:

"Wizards is testing a new mulligan rule at Mythic Championship London. If you mulligan you choose to draw back up to seven cards and then when you finish mulliganing you put a card on the bottom of your library for each time you mulligan. No scrying."

Yikes.

If anyone is curious, the odds of failing to finding a 4-of in a 60 card deck with 6 mulligans (as 7 mulligans serves no point) is (1-0.40)^7 = 2.8%. This doesn't include Serum Powder and yes, I am clearly referring to dredge here.

This is a huge change and more powerful than the proposed change of "take a scry for each mulligan" as looting improves the quality of cards in your hand and you would have to choose to keep a hand before scrying under the old system. I think this would have a pretty significant impact on mulligan decisions and vintage gameplay and it might just be wrong to keep a hand without Power in Vintage if the new rule is implemented.

And per Hipsters of the Coast's tweet:

Ian Duke says that if the new mulligan rule sticks, Wizards will take a look at the Banned & Restricted list and reevaluate cards that might be a problem/take too much advantage with the new mulligan

So that might stir the pot as well...

Edit: Fixed the math

@chubbyrain said in Proposed New Mulligan Rule for Mythic Championship London:

If anyone is curious, the odds of finding a 4-of in a 60 card deck with 6 mulligans (as 7 mulligans serves no point) is (1-0.40)^6 = 4.7%

I think Markdown may have fucked your math display here. (1-0.40)^6 is .6^6 is 5.6 . Also, I'm pretty sure the odds of finding a four-of in six to-seven mulligans is far higher than 4.7% .

Its probably easier to leave the mulligan rule as is for eternal formats than have to deal with multiple rounds of bannings/restrictions before they got this right. The odds of them deciding to restrict bazaar and workshop are lower than the failure rate of finding a bazaar w/ serum powders. I mean do you keep bazaar and restrict what?, grave troll, narcomoeba, and serum powder? Maybe hollow one? Is leyline of anticipation.dec automatically tier 1? Would we be locked into additional shops restrictions? How unfun would game 2/3's be on the play vs blue.dec when they can aggressively mull to FOW? Do all these things balance out in the wash? Far too many unknowns for my liking when considering nearly unlimited card pools.

Also (chuckles to self) the idea that MODO would program the new mulligan + Serum Powder interaction correctly out of the gate is low probability as well.

@p3temangus said in Proposed New Mulligan Rule for Mythic Championship London:

Also (chuckles to self) the idea that MODO would program the new mulligan + Serum Powder interaction correctly out of the gate is low probability as well.

I don't think so, they probably have a mulligan counter or something and that doesn't move up if you use powder, which wouldn't change with the new rule.

BTW, if that happens MTG will be very different. I don't know yet how every piece will move, at least G2/G3, decks that have very key pieces (dredge, survival, to some extend shops, etc) will have more chance to find their pieces, as well as their opponents will have more chances of finding hateful keepable hands. The only thing I'm sure about is that it would change things a lot.

@thecravenone 0.6^6 is 0.046656 or 4.7% with rounding. I'm not sure how you arrived at 5.6 (is this number a percent or just decimal?).

And thank you, I omitted a key word. The 4.7% is the odds of NOT finding a 4-of. I fixed it in original post.

Came here to post this. Seems absurd.

This new mulligan rule without Serum Powder or Scry is better than the current rule with Serum Powder + Scry

New rule: 4.7% chance of miss = 95.3% chance of hit
(should also consider the top card of the deck if you're on the draw, with 6 known misses on the bottom of the deck)
Current rule, with Powder + Scry: 94.2% chance to hit during mulligans, 95.0% chance to hit after scry + draw.

So this new rule would be an upgrade without Powder. With Powder the math gets complicated (you could exile multiple Serum Powder at once) but Powder should eliminate ballpark 2/3 of the mulligans to oblivion. In this case, the miss rate would fall to about 1.5%. My suspicion is that because you always Powder for 7 under the new rule it has a little more impact than that and you get the miss rate down to 1%ish

In short: yes please

One source of the mulligan numbers is here: http://www.archive.themanadrain.com/index.php?topic=48196.0

@ajfirecracker I'm not sure of the official language of the rule, but one comment on my Twitter said that you would put the cards back before deciding whether or not to mulligan (and being able to Powder). Which seems like an interesting implementation but would make Powder less strong. If you plug the numbers in for 8 success in the hypergeometric calculator, you get a 0.17% chance of not finding a Bazaar or Powder. The actual math with Powder is too complicated for me but I think you are down in the <1% range.

While dredge is the poster child for "what does this do to opening hands" I think the ability to mulligan aggressively for silver bullets is likewise a little brain melty.

Leylines, major hate pieces, power, force of will...the game would change radically if you could actively go fishing for them and potentially still come away with a keepable hand.

If I had to predict what will happen, I think Serum Powder might get restricted preemptively. I actually think Dredge will be fine from a balance perspective within the Vintage metagame...the failure rate with 1 Powder is going to be slightly lower than it was before with 4 Powders and the old mulligan rule. This gets countered by increased odds of finding hate. Dredge is probably a little better but not oppressively so.

I think in terms of other decks, the average quality of a mulligan goes up considerably and you'll see more broken openers and consistent combo draws. It will affect vintage play significantly.

I think there's a real chance Dredge is oppressive with this new rule.

A build like Pitch Dredge becomes much, much stronger with more cards in hand on average and better ability to filter good cards into its opening hand. Even an alternate plan like Dark Depths becomes much more attractive when you can filter more deeply to find it.

I'm trying to find the MTG Arena angle that's almost certainly behind this, but I'm coming up blank so far.

Was talking about this in the Dredge discord, someone pointed out that you have 7 attempts (7 card hand, 6 card hand, etc. to 1 card hand) so it's only about 2.8% to whiff without any Serum Powder or other enhancers. I think you forgot to count your opening 7 prior to any mulligans.

So this cuts the failure rate in half and frees up 0-4 slots for something else. Seems good.

@p3temangus said in Proposed New Mulligan Rule for Mythic Championship London:

Its probably easier to leave the mulligan rule as is for eternal formats than have to deal with multiple rounds of bannings/restrictions before they got this right.

While this might true, I think in the long run it's probably not a good thing if different formats follow different basic rules of MTG!

Just curious but how much would this increase odds of Mox/crypt/lotus + Orchard + Oath turn 1? They are all 4+ ofs, can anyone do the math?

@cambriel said in Proposed New Mulligan Rule for Mythic Championship London:

I'm trying to find the MTG Arena angle that's almost certainly behind this, but I'm coming up blank so far.

It's because of the e-sports push. They took some criticism at whatever PT it was last year after LSV anticlimactically exited the top eight when he had to mull to four. Non-games like that are bad for the streaming numbers, which is what they're focusing on now.

@craw_advantage said in Proposed New Mulligan Rule for Mythic Championship London:

@cambriel said in Proposed New Mulligan Rule for Mythic Championship London:

I'm trying to find the MTG Arena angle that's almost certainly behind this, but I'm coming up blank so far.

It's because of the e-sports push. They took some criticism at whatever PT it was last year after LSV anticlimactically exited the top eight when he had to mull to four. Non-games like that are bad for the streaming numbers, which is what they're focusing on now.

Still, that is probably the only game I remember from that PT...

Dredge opponents can also mulligan to Leyline game 2. So I don’t think this would make Dredge oppressive. Better, sure, maybe better to the point of maindeck graveyard hate, but nothing that is restrictable.

@serracollector said in Proposed New Mulligan Rule for Mythic Championship London:

Just curious but how much would this increase odds of Mox/crypt/lotus + Orchard + Oath turn 1? They are all 4+ ofs, can anyone do the math?

Assuming 4 Orchard, 4 Oath and 7 Mox/Lotus/Crypt and assuming you mulligan until you have T1 Oath, roughly 32% compared to 15% under the existing mulligan rule.

What I find irritating about this rule is that no one asked for it. When the Paris mulligan was created in the 1990’s it was created by players to solve a real problem.

The original mulligan rule was not good and in Type 1 it could be abused by no land decks or very heavy land decks by getting free mulligans.

This new mulligan rule looks like a solution without a problem. Card games have variance and sometimes you lose to variance.