Slay the Spire

Word Play modeled its modifier perks on Slay the Spire's relics. Mark Brown's Word Play has 120 modifiers, passive perks that pay off under the right conditions, and took Slay the Spire's relics and Balatro as reference points.

He wrote down requirements first, including ordered triggering and easy testing, which showed a chain of if statements would fail.

Revealing enemy plans before the player acts ended near-random play. Early builds hid what enemies would do until after you ended your turn, so players did not know whether to block or attack. Moving the enemy's random choice to the start of the turn and showing intent icons let players strategise, and the game became far more fun.

It turned output randomness into input randomness and enabled smarter plays and synergies. Quote: "Output became input."

Win-rate data can mislead; check why a card appears in winning decks. Madness showed up in many winning decks, which looked like it was overpowered, but a late-game event simply handed it out regularly.

Mark uses it to argue for being data informed, not data driven.

Card draws are dependent probability, which is what makes synergies plannable. Drawing a card changes what is left in the deck, unlike independent dice rolls, so players can build and plan around combinations.

Starting bonuses only after reaching the first boss discourage reroll restarts. Slay the Spire gives a bonus at the start of a run only if you reached the first boss last time, so players work with what they are given instead of restarting until they get lucky.

Mark contrasts this with Spelunky, where a starting crate can give a jetpack or shotgun, blurring skill and luck.

Revealing enemy plans before the player acts ended near-random play. Early builds hid what enemies would do until after you ended your turn, so players did not know whether to block or attack. Moving the enemy's random choice to the start of the turn and showing intent icons let players strategise, and the game became far more fun.

It turned output randomness into input randomness and enabled smarter plays and synergies. Quote: "Output became input."

Cards that hint at their partners let players spot combos themselves. Body Slam deals damage equal to your block, which points straight at Entrench (doubles block) and Barricade (block no longer resets each turn). Heavy Blade counts strength three times, or five when upgraded, which points at Inflame and Limit Break.

No tutorial explains the pairing; the card suggests it. Relics extend this: Anchor gives 10 block and Red Skull gives 3 strength below 50% health. Quote: "Immediately, an idea starts to form."

A big combo feels thrilling because normal damage numbers are small. Mark Brown's Silent deck combined zero-cost shivs with three relics: bonus damage for zero-cost cards, a random card on each exhaust, and no discard between turns. Storm of Steel then turned a full hand into nine upgraded shivs of nine damage each, 81 damage in one turn.

Skipping the discard filled the hand to the 10-card maximum after a few turns, and each exhausted shiv added a random card. The combo made even the biggest enemies a pushover. Quote: "it feels utterly thrilling to do a massive combinatorial attack."

Power players discover feels earned, so they feel smart, not just strong. Players notice a link between cards they chose and assemble it, which can feel like getting one over on the developer, even though the devs planned it.

Quote: "You weren't simply given the tools to be powerful - you found them."

Synergies multiply depth while keeping the parts to learn few. Twenty cards that work alone give twenty strategies; ten cards that combine give a hundred, with half as many cards to learn.

Mark Rosewater calls this "lenticular design": simple on the surface for new players, deep for advanced ones.

Synergies that need setup, across turn, combat and run, feel best. Per turn means card order, like making an enemy vulnerable before attacking. Per combat means building over several turns, like stacking poison before tripling it, banking energy, or using Setup and Thinking Ahead to get two combo cards into one hand. Per run means choosing cards, relics and shop buys.

Turn-level planning is the easiest and comes up every couple of minutes. Quote: "A synergy that comes together too easily isn't quite as fun as one that requires a bit of set-up."

Making card removal and skipping matter pushes players toward lean decks. Junk cards and curses dilute the combo cards you want to draw, so the game lets you remove cards at shops and special events and makes skipping a reward as important as taking one.

Quote: "Slay the Spire makes skipping cards, or outright getting rid of them, just as important as adding them to your deck."

Adding cards one at a time makes deck building approachable. The deck starts with a few simple attack and block cards and grows through a choice of three random cards after each win, plus events and the shop. Mark finds choosing from hundreds of cards in Magic and Hearthstone overwhelming; here the thrill of synergies comes without that paralysis.

Quote: "you piece together your arsenal of cards over the course of the game, one at a time."

Random offers force players to build around what appears, not a list. Players cannot pick perfect synergies, so they improvise connections from the early cards and relics they are given. The hope that this run will produce a perfect synergy adds to the pull to replay.

Mark says he isn't sure whether that pull is addiction or engagement. Quote: "You've got to think on your feet, and find connections where you can."

Permadeath stops an optimal combo from going stale or breaking balance. Strong synergies become strategies you would repeat forever, but runs restart after a death, or after a win with a new character or higher difficulty. Mark's shiv deck fell to the Time Eater boss and he has not seen that card and relic mix since.

Quote: "this doesn't ruin the balance forever."