Meet Your Four Opponents

Cell Division ships with four AI opponents — Easy, Medium, Hard, and Elite — and they’re genuinely different from each other. Not the same bot with more handicap. Four personalities, each tuned to the kind of game you’re in the mood for. Here’s what each one is doing, why they feel the way they do, and how to tell them apart.

Four opponents, one app, no server

All four tiers live inside the app you downloaded. There’s no cloud call, no account, no subscription behind any of them. You can play Cell Division in airplane mode, on the subway, on a plane, or with your phone set to “no data roaming” abroad, and the opponent plays exactly the same way it does on Wi‑Fi. Every tier responds instantly — you’ll never see a “thinking…” spinner.

Easy — loose and a bit random

Easy is the tier for your first few games, or for when you want to beat something without any pressure. It plays into open space most of the time, avoids the edges, and occasionally makes a choice that doesn’t quite make sense. That last bit is on purpose: if Easy always played the same way, it would feel scripted, and you’d beat it once and be done. A little unpredictability is how a learning opponent keeps its job interesting.

You should be able to beat Easy within a few tries. If you can’t, the difficulty ladder is doing its job of easing you in — no shame in staying here.

Medium — greedy for points

Medium is the most predictable of the four. Every turn it looks at every legal move, works out which one scores the most points right now, and plays that one. If you make a move that hands it a bonus, it will take the bonus. If you leave it a clean play-for-6 square, it will take the six.

Medium is the tier to practice against if you want to see the scoring clearly. It won’t do anything sneaky — it also won’t miss anything obvious. Players who master Medium usually do it by learning not to set up big scoring cells for the opponent.

Hard — punishes mistakes

Hard is where the AI starts looking at the board as a whole position rather than just the next move. It was trained by playing itself — tens of thousands of games in a training loop — and it learned to weigh things Medium ignores: the shape of your territory, where the edges are, how crowded a neighborhood is becoming, whether a cell is bridging two of your groups.

What that feels like at the table: Hard doesn’t chase every point. It plays some moves that look quiet at first and turn into traps two turns later. It punishes sloppy openings. It exploits boards where you’ve committed too heavily to one corner. You can beat Hard — lots of players do — but you have to be playing carefully the whole game, not just when a big scoring square appears.

Elite — a tiny neural network

Elite is the tier that stops being about rules and starts being about intuition. Under the hood it’s a small neural network — a completely different kind of opponent from the first three. Instead of scoring each move with a formula, it looks at the whole board and picks the move it would have picked after watching thousands of games played by a much stronger program.

In practice: Elite makes moves that look considered and a bit unusual. It sets up threats several turns in the future. It doesn’t fall for the cheap tricks you might land on Hard. It will take a corner or a pivot that you didn’t realize was valuable. If you’ve played Go or Othello, it’s a similar feeling — the moves don’t all announce themselves.

Which tier should you play?

• new to the gameEasy for a few games until the scoring clicks, then switch to Medium.
• learning to read the boardMedium. It rewards careful counting and punishes nothing else.
• looking for a fightHard. It’ll beat you the first few times until you notice how it punishes sloppy moves.
• want a genuine challengeElite. Expect to study your losses.

A few things all four have in common

• no account requiredSingle-player needs no login, no email, no subscription. Open the app, pick a tier, play.
• no network callsEvery tier runs entirely on your phone. The moves aren’t coming from a server somewhere — they’re being computed on the device in your hand.
• no pay-to-winEvery difficulty tier is in the free version of the game. We’re never going to sell access to “a harder AI.”
• same strength on every deviceThe AI plays the same on a flagship and on a five-year-old Android. Older phones don’t get an easier opponent.

For developers

The full engineering writeup — the 14 board features, the 13 trained weights Hard ships with, the PPO self-play loop, and the AlphaZero teacher-student pipeline Elite comes out of — lives on the Island & Pine studio blog: Four difficulty tiers, two model families. For the shipping side of Elite specifically — how a PyTorch model ends up as a 262 KB file inside the app bundle — there’s Shipping a CNN game AI on-device in Expo with ONNX.