Marvel Snap Card Impact: Win Δ & Play %

Every deck on SnapComplete has a premium panel that grades it card by card. Tap the eyeball row under any deck on the Decks page or your own My Decks to expand a ranked list of all twelve cards. The Win Δ and Play % buttons toggle two views: how the deck's winrate differed depending on whether each card was drawn, and how often you played each card once you drew it.

Win Δ: Winrate When a Card Is Drawn vs Not Drawn

Win Δ compares two winrates: how often the deck won in games where you drew the card, against how often it won in games where you did not. It is shown in percentage points (pp). It has nothing to do with when in the game you draw the card, only whether the card was drawn at all.

Drawn/not-drawn stats, including Play %, count only games that reached their final turn. Retreats on the final turn count; earlier exits do not. Short games give every card fewer chances to be drawn, which skews the comparison. The deck's winrate and game count at the top still include every game, and the small +/- beside each When Drawn and When Not Drawn number compares it to the winrate or cube rate at the top.

Domino, Quicksilver, and Agatha show 0pp and rank with the other cards because they are always drawn in a full game. For other cards, — appears only when there are no drawn or no not-drawn games in the period.

A positive number means the deck won more often in the games where that card was drawn. A negative number means it won more often in the games where that card stayed in the deck. The top card is labeled MVP, the bottom Weakest, and the collapsed panel shows just those two.

Take Aurora in the deck below, at +7pp: this deck won 61.9 percent of its games when the card was drawn and 55.0 percent when it was not, a 7 point gap that ranked Aurora MVP. A card near 0pp won about the same whether or not it was drawn.

Two things to keep in mind. Win Δ is winrate only: the panel also shows each card's cube rate, but cubes never feed the ranking. And the bigger the gap, the more the deck's record swung on whether that card was drawn. Zombie Galacti is a good example: in the deck below it topped the list at +23pp, far above every other card, with the deck winning 57.4 percent of the games where Galacti was drawn and only 34% (57% - 23pp) in the games where it was not.

Only the Community Decks Page Smooths

On the community Decks page, small samples are pulled toward the deck's average in those same final-turn games so a handful of games can't produce an extreme number. Larger samples need less adjustment. This is Bayesian smoothing.

Your own My Decks is never smoothed. Every Win Δ there is your exact winrate when the card was drawn minus your exact winrate when it was not, however few games that is.

Play %: How Often You Play a Card Once You Draw It

Play % is simpler. Of the games where you drew the card, how often did you actually play it? No smoothing on either page. The card you played almost every time you drew it sits at the top as Most; at the bottom, Least, is the card you most often kept in hand instead. A card turns cyan once you played it in at least two of every three draws.

Both views are premium, on every deck on the site and every deck of your own.