Movement costs is the one thing I haven’t really figured out yet. Partly it is because how this is implemented seems to differ from game to game. In some games big units are slowed down if any of its tiles enters a tile of difficult terrain, while in others the unit ignores difficult terrain unless all occupied tiles are difficult terrain. The other issue is that tiles in the toolkit can have varying costs depending on which direction they are entered from. This means that I cannot simply check all occupied tiles and see if they have a cost or not, but I have to check several different edges. This quickly becomes very costly, and multi-level grids makes this even more difficult still. I will try to find a way to precalculate these costs so that there is no performance impact during actual gameplay, but I still want something that is fairly performant during setup. I will find a solution and have a few ideas, but I’m not sure what I’ll end up with using.