Probability of finding a Bazaar with Serum Powder using Vancouver-Mulligan:
94.2% (fails every ~17 games)
Probability of finding a Bazaar with Serum Powder using London-Mulligan:
99.5% (fails every ~200 games)
Probability of finding a Bazaar without Serum Powder using London-Mulligan:
97.2% (fails every ~35 games)
Seeing those numbers it still feels obvious to run the powder, but there are things to consider:
In game 2/3 a necromancer doesn't only pray for bazaar, he also needs to hope to find plan b, usually an antihate and a land.
Keeping in mind dredge is a deck that's totally willing to mull to one, finding a Bazaar without using powder on mull to 3 cards is 92.2% (London mulligan).
On the other side, you'll get the odds of ~1:3 to find a bazaar with 4 cards in hand by activating powder ~33%, but are those random other 3 cards enough?
I would like to argue, its better to go down to 3 cards, and pick with 39,9% chance your bazaar and force+pitch/land+claim/misstep+dredger/unmask out of 7 to go along with it (or miss and get two rolls with 39,9% chance again).
Like mentioned, at this point we had the overall chance to find a bazaar by 92,2% anyway (no powder used).
While its true that villain will also have a better chance to find his hatepieces, he isn't really capable of utilizing the London mulligan as much as the necromancer does, after all a (e.g.) Leyline alone doesn't win the game.
Keeping this post math-themed: villains overall chance of Leyline with one mulligan is 63.9%, even with a mulligan to 5 cards its "only" 78,3% (compared to Vancouver: 61,1% / 72,8%)
I would like to argue our increased chance of finding a bazaar+ answer against hate makes up for that even without Powder.
The benefit of those 4 free slots:
While vintage became way faster in the last years dredge needed to adapted, especially winning game one is important, because the odds of winning decreases significantly in postboardgames (<30% per game(?).
Some people call it unfair, but cards like Force of Will and Unmask are necessary in "the new" meta to keep up with those fast builds like Storm, Outcome and even Shops,
but including those cards took a lot of space in the decklist, people even started to cut out the core engine cards to make room for Force and co. and push the high variance of dredge even further.
That's just wrong, in all formats, in all decks.
I like to link to a video at this point: https://www.youtube.com/watch?v=QkW2BY5f7zo
a little OT, a little old, but worth a watch for all who start tweaking on dredge.
Back to OT, my first assumption to Powder post 10th of April is unclear, I would consider it in large tourneys, but when it comes to Leagues, I got this paradox feeling a little more gamble could make dredge even more consistent..
Sadly, putting all those variables into an equation is too much for me ^^
what are your thoughts?