I Analyzed the Optimal Deck Size for Watcher

In this article, I examine the optimal deck size in Slay the Spire.

…or at least, that’s how I started writing it.

The conclusion is this:
The optimal number of cards depends on the type of deck.

However, “optimal deck size” is a classic topic in card games.

And thinking about the optimal number of cards is just as fun as asking,
“If Deck A and Deck B fought seriously, which one would win?”

I got excited, lost my cool, and went for it.

Ideally, I wanted to analyze every character, but I only had around 20 run histories each for Ironclad, Silent, and Defect.

That wasn’t enough to see any meaningful trends.

So instead, I focused on Watcher, where I could check over 100 run histories, and analyzed the optimal deck size there.

First, the conclusion.

If you enjoy looking at data, read on.

Thinking About Watcher’s Optimal Deck Size

First, here’s the graph.

The vertical axis shows the number of winning decks.
The horizontal axis shows the number of cards.

The most common deck size is 30 cards, followed by 32 cards.
The overall range is from 20 to 40 cards.

Decks with 25–35 cards account for over 50% of all wins.

[Bonus] Deck Size Graph by Character

Finally, a small bonus as a kind of memorial.

These are deck size graphs based on winning decks for each character.

From top to bottom: Ironclad, Silent, Defect, and Watcher.

The horizontal axis is deck size.
The vertical axis is number of wins.

Number of winning decks analyzed ▼

• Ironclad: 27
• Silent: 14
• Defect: 20
• Watcher: 129

Honestly, aside from Watcher, it’s hard to tell anything!

 

The end.

※ Source data ▼

[World Rank #1] Watcher’s Longest Win Streak – All Decks