Puzzles that can always be solved

A puzzle game makes a promise: there is a way through. Every level in our new games keeps that promise, because a computer has checked it before it ships. These are the three tools we use most.

1. Build the level backwards

The simplest way to guarantee a solution is to build the level from its solution. In Surprise Cube we fill the box from the inside out. Each new block gets an arrow that points along a clear path out of the shape as it is so far. When the box is full, taking the blocks out in reverse order solves it, so every box can be emptied.

Honk! Bus Jam works the same way. Vehicles are placed one by one, each with a clear road out past the ones placed before it. The passenger queue is then built from a valid exit order, and a separate solver replays the level with the real number of waiting bays to make sure it still works.

2. Let a solver play every level

Some puzzles cannot be built backwards, so a solver plays them instead. Fishbowl and Ring Twist use exact solvers that find the fewest possible moves. That number becomes the level's par, and you get three stars for matching it.

In Cat Corner the solver does something stricter. It checks that every puzzle has exactly one solution, and that you can reach it by logic alone, without ever guessing. Boards that need a guess are thrown away.

Topple! runs on physics, so its check is different: every level has to stand still on its own for a few seconds, and an autopilot has to clear it with the cannonballs you get.

3. Grade the difficulty

Solvable is not the same as fun. We grade every level by how much work it takes: how many logic steps in Cat Corner, how often a simulated casual player wins in Honk! Bus Jam and Pixel Bees. Then we order the levels so the difficulty climbs like a saw: a harder level, then a breather.

New twists, one at a time

New ideas such as hidden fish, padlocked rings or mystery vehicles first appear on an easy level, with a one-line tip. You learn the twist before it is used against you.