Methodology
Everyone builds a tier list differently. I have chosen to build mine based on MTGO Challenge results (As collected by Joe Dyer and the Legacy Data Collection Discord). A data driven approach helps inform the feelings that I have based on my experiences playing decks and playing against decks in multiple settings. For this tier list, I am looking at all of the data since the banning of [[Expressive Iteration]] and [[White Plume Adventurer]] The best way to use a tier list is to help choose what deck to play or how to tune a deck to beat a metagame. The decks I will be ranking are the most played in the forma,t and I will not be ranking every Legacy deck ever played — there just is not enough space for all of the decks. Ranking decks within tiers is too close to splitting hairs. Within a tier, decks will simply be alphabetized.S Tier
A deck that will consistently place one or more copies in a challenge top 8. Normally these decks reach the threshold to be "bannable". They have strong win rates and play rates and players will always consider warping their sideboard, main deck, or even archetype selection based on these decks. An S-tier deck has almost no very bad matchups and few bad matchups among commonly played decks in the format. If you are not playing one of these decks, you are either wrong or have a very good reason to not play the deck.
A Tier
Decks that consistently has a copy in the top 8 of a challenge. It probably will not top 8 every challenge either, but should be in most. An A-tier deck is a strong force in a metagame, but not overwhelming. These decks have weaknesses, though bad matchups tend to have lower play rates. Choosing one of these decks for a tournament is almost certainly a good place to be.
B Tier
Strategies that will not make most challenge top 8s either due to low power level or lower play rate. A B-tier deck making a top 8 would not be shocking, but you would expect zero copies in most top 8s. These decks maintain an exceptional win rate against some higher tier decks, but lower against other decks. To choose to play a B-tier deck in a tournament is to put yourself at a disadvantage and be willing to play a specific metagame read.
C Tier
Often specialist decks that will rarely make top 8s and only then in the hands of archetype masters. Generally, good players of these decks grind them often and eventually get enough wins to top 8, but seeing any of these decks in the top 8 is a surprise. The play rate of a C-tier deck is generally in the one to two players per event space. While they have some good matchups, there are likely format pressures keeping them from being higher tier or the strategy might be inherently weak.
D Tier
Archetypes that are just underpowered or rarely played. It is sometimes surprising to see these decks registered in any amount in a challenge.
The Tier List
S Tier
No Decks
A Tier
B Tier
C Tier
The Metagame
Rating my Rating
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