The roster
Every team in ChasinBase fields nine positions: catcher, four infielders (1B/2B/SS/3B), three outfielders (LF/CF/RF), and one designated hitter — plus a starting rotation built around your ace. You aren't drafting an entire 26-man roster. You're building the core nine bats and the arm that determines the staff's quality, and the sim fills in the surrounding pieces from league-average baseline contributors.
Positional eligibility matters. A career first baseman can't slot in at shortstop — the slot machine will only surface players whose primary position fits the open seat. That's why building a balanced roster gets harder the deeper into the draft you go.
Classic mode
Classic is the original ChasinBase loop. For each open roster slot, you pull the slot machine, it spins through eligible players from your selected era, and lands on one. You take that player. No re-spins, no swaps — the next slot machine is right behind it.
Classic rewards conviction and patience. You can't engineer the perfect team. You can only keep showing up and seeing what the draft hands you. A bad spin at catcher isn't season-ending; the sim weights your team's total run scoring and prevention, so a deep middle of the lineup can carry a weak position.
Diamond IQ mode
Diamond IQ replaces the slot machine with a three-card choice. Each slot, you see three eligible candidates and pick one. This rewards real baseball knowledge: do you know that a league-average 4.0 WAR shortstop is more valuable than a great-glove first baseman? Do you understand which dead-ball-era pitchers stand up to era-adjusted modern grading?
Diamond IQ teams typically win more games than Classic teams because you can route around obvious weaknesses, but it also exposes mistakes. Picking the wrong player from a tough three-card set leaves real wins on the table.
Team Mode
Team Mode locks the draft pool to a single franchise. You're building the all-time Dodgers, all-time Cubs, all-time A's, etc. — only players who suited up for that franchise are eligible. This is the mode for fans who want to see what their team's true ceiling looks like when you stop at nothing but the franchise's own history.
Head-to-Head (online)
Head-to-Head is the live online mode. You queue up, get matched with another player on the same ruleset and era, both players ready up, and then the snake draft begins. You alternate picks (1–2, 2–1, 1–2, etc.) from a shared player pool, so every pick you skip is one your opponent can grab.
When both rosters are full, the engine sims a season for each team simultaneously. Bigger run differential wins. Match results are recorded to your H2H stats and the daily leaderboard.
Eras
Three era filters are available everywhere:
- All-Time — entire MLB history is eligible (1871–present).
- Modern (1970s+) — only players whose careers started in 1970 or later. No Ruth, no Cobb, no Johnson.
- 2020s — current-era players only. Trout, Ohtani, Judge, Acuña, Soto.
Pick your era before you queue up. In Head-to-Head, you're only matched against players who chose the same era, so the draft pool is identical on both sides.
How wins are calculated
Each completed roster is graded on aggregate runs scored (from your lineup's era-adjusted offensive ratings) and runs allowed (from your ace's quality, weighted against the league-average rotation behind them). Those two numbers feed a Pythagorean expectation formula — the same model real baseball analysts use to predict win totals.
The model then adds variance: a 95-win true-talent team might finish anywhere from 87–75 to 103–59 depending on luck. That's why the same drafted roster doesn't always produce the same record. Real baseball isn't deterministic either.
Why 117?
117 wins would tie the modern MLB single-season record (2001 Mariners and 1906 Cubs). It's the ceiling. Hit it, and you've built an all-time team. Most drafts don't get there. That's the point.