Daily Brains · one Hold'em hand a day. Price every call, guess your equity, play it the way the maths says.
Massachusetts Hold'em is the poker puzzle in Daily Brains (/daily). Every day everyone is dealt the same Texas Hold'em hand at a six-handed table and plays it against one scripted opponent whose range of possible hands is defined in advance. There are four decisions, one per street (preflop, flop, turn, river): fold, call or raise (or check or bet when nobody has bet), plus an optional guess at your equity. A real equity calculator grades each play by expected value and explains the right answer. It is a decision puzzle with play money only: there is no wagering of any kind.
STORY & LORE
The room
A late game somewhere between Southie and the Cape. Five regulars rotate through the opposite seat: Dot from Dorchester (tight), Nell from Nantucket (very tight), Sully from Southie (calls everything), The Professor from Cambridge (balanced) and Wicked Pete from Worcester (hyper-aggressive). Everyone else at the table folds; it is always you against one of them.
Why “Massachusetts maths”
Real poker EV depends on every future street. To keep each decision a clean puzzle, the game scores each play as if the hand checks down from that point: your equity is what you win on average. That is the same simplification every pot-odds lesson uses, and it is stated in the rules and in each breakdown.
HOW IT PLAYS
A day's hand
The hand is generated from the puzzle number, so it is the same for every player. Preflop you face a raise: an open from an earlier seat (you are in the hijack, cutoff or button), a small-blind raise while you are in the big blind, or (Thursday on) a 3-bet after you open. After the flop the opponent always acts first and you close the action, so every street has exactly one decision for you.
Your options
Facing a bet: fold, call, or raise to one of two sizes (preflop 3-bet or 4-bet sizes; after the flop 3× the bet or a pot-sized raise; capped at all-in). Facing a check: check, bet a third of the pot, or bet three quarters. Keys 1 to 4 pick an option; ← → nudge the equity slider.
How the opponent plays
The opponent's range is a list of real two-card combinations, filtered street by street by what they did, so card removal is exact. Preflop ranges come from a ranked list of the 169 starting hands (Chen points) and each opponent's open, 3-bet and defence settings. After the flop they bet their best made hands (a real pair or better that uses their hole cards), semi-bluff draws if that is their style, and bluff a fixed share of their air. Against your bet or raise they continue with the top stickiness × (pot ÷ (pot + your chips))^0.6 of their range; the strongest part of that (two pair or better after the flop) shoves all-in instead of calling, and the rest fold. Facing a shove, you automatically make the maths-correct call or fold. Their actual cards are drawn from the range they end up with, so they always take the action their range takes.
The maths
Equity is computed against every combination in their range: exact enumeration of every turn and river on the flop, every river on the turn, and a straight comparison on the river; preflop uses a seeded Monte Carlo (160 boards per combination), identical on every device. EV of fold = 0; check = equity × pot; call = equity × (pot + call) − call; bet or raise = fold% × pot + call% × (equity vs the calling hands × final pot − chips added) + shove% × (the better of calling or folding to the shove).
Scoring
Each street: 150 for a Perfect play (the best EV, or within 2% of the pot of it), 90 for Close (within 10% of the pot), 0 for a Leak. Your equity guess scores up to 50: full marks within 3 points, then 50 × (1 − (error − 3) / 22). Win the pot (they fold, or you win at showdown) for a 200 bonus; a split pot gives 100. If the hand ends early, each street you skip scores the same as the play that ended it. The best day is 1000. Score 400 or more to keep your streak.
The breakdown
After each decision you see your grade, your true equity, the price to call, your guess, the EV of every option in big blinds (the best one starred), a one-line reason (for example “The price is right: you need 29% and have 46%. Raising is worse: they fold 6% and you have 48% when called”) and what happened next. The opponent's current range is one tap away as a 13×13 grid.
How days are chosen
The generator deals candidate hands and walks the main line (the best play every street) before the opponent's cards are dealt. A day is kept only if all four decisions happen, every street has a clear best play by the weekday's margin, at least two decisions are priced calls, the equity is not lopsided all the way, and later in the week at least one decision is a raise, a bet or a fold. About a third of days prefer a preflop raise as the answer, and from Thursday a few days end with a disciplined turn fold. The attempt each day settles on is precomputed in days.js for the first 730 days so a phone deals the hand in one pass.
Sharing
The share text is spoiler-free: the hand number, your score, one square per street (■ Perfect, ◧ Close, □ Leak), the weekday and your title, e.g. “Massachusetts Hold’em #34 · 820/1000 / ■ ■ ◧ □ Pre Flop Turn River”.
THE WEEK
| Day | Level | Pots | Opponents | Clear best play by |
|---|---|---|---|---|
| Monday | Gentle | Facing an open | Dot, Nell, Sully | 4% of the pot (price shown) |
| Tuesday | Mild | Open, or blind vs blind | Dot, Nell, Sully, The Professor | 3% (price shown) |
| Wednesday | Steady | Open, or blind vs blind | Dot, Nell, Sully, The Professor | 2%, one move to find |
| Thursday | Tricky | Any, 3-bet pots appear | Dot, Sully, The Professor, Pete | 2%, turn folds possible |
| Friday | Sharp | Any | Dot, Sully, The Professor, Pete | 2% |
| Saturday | Devious | Mostly blind vs blind, some 3-bet pots | Sully, The Professor, Pete | 2% |
| Sunday | Fiendish | Blind vs blind and opens, the most 3-bet pots | The Professor, Pete | 2%, two moves to find |
THE REGULARS
| Opponent | Style | Opens | Bets for value (flop/turn/river) | Bluffs air | Stickiness | Shoves back |
|---|---|---|---|---|---|---|
| Dot from Dorchester | Tight | 0.8× standard | 40% / 35% / 30% | 4% | 1.05 | top 30% of continues |
| Nell from Nantucket | Very tight | 0.7× | 32% / 28% / 25% | never | 0.85 | top 40% |
| Sully from Southie | Calls everything | 1.15× | 30% / 28% / 25% | 5% | 1.5 | top 10% |
| The Professor from Cambridge | Balanced | 1.0×, semi-bluffs | 42% / 36% / 32% | 14% | 1.2 | top 30% |
| Wicked Pete from Worcester | Hyper-aggressive | 1.5×, semi-bluffs | 55% / 50% / 45% | 40% | 1.3 | top 40% |
POINTS
| Part | Points |
|---|---|
| Perfect play (per street) | 150 |
| Close play (within 10% of the pot) | 90 |
| Leak | 0 |
| Equity guess within 3 points | 50 (down to 0 at 25 points off) |
| Win the pot / split | 200 / 100 |
| Best possible day | 1000 |
REWARDS
| Event | Reward |
|---|---|
| Finish a day with 400+ | 15 Tickets |
| Perfect day (four Perfect streets) | +25 Tickets |
| Shuffle Up (first 400+ day) | Bronze · 10 Tickets |
| Dead Eye (guess within 2%) | Bronze · 10 Tickets |
| Showdown on the Common (win at showdown) | Bronze · 10 Tickets |
| Get Outta Here (they fold) | Silver · 15 Tickets |
| Disciplined (a Perfect fold) | Silver · 15 Tickets |
| Wicked Smaht (four Perfect streets) | Silver · 20 Tickets |
| Mind Reader (every guess within 5%) | Gold · 30 Tickets |
| Regular / Seven Nights a Week / Fixture at the Table (3 / 7 / 30-day streak) | 15 / 40 / 100 Tickets |
| Secret | Gold · 20 Tickets |
VERSION HISTORY
- Launch version in Daily Brains.
- One seeded Hold'em hand a day against five scripted regulars with defined ranges; four decisions with EV grading, an optional equity guess, and a win bonus.
- Own 7-card evaluator (checked against all 2,598,960 five-card hands) and equity calculator: exact after the flop, seeded Monte Carlo preflop.
- Vector cards (four-colour suits, framed court cards), felt table with drawn chips, a 13×13 range viewer, a five-step drawn rules deck that opens only from How to play.
- Streaks, statistics, spoiler-free share line, progress saved after every decision and restored on reload. Rated Teen by default because it is a poker game, although no money of any kind is staked.