Thanks, Kev. I think 21 would be a lot easier than say 23, as you could simply use regular pathfinding and have half the body trail behind on the previous tile. This would cause issues with diagonal movement on square grids, though, which is why I assume they take up 2*2 tiles when moving diagonally. I would need to set up some hybrid system, in that case, but I think that is something I could add on top of what I’ve already got at some later point.
I just recalled that Heroes of might and magic II and III had units taking up 21 tiles, but this is pretty simple since they always face left/right and never rotate. I’m having trouble finding a TBS computer game with multi-tile units that take up an unequal number of tiles where both dimensions are higher than one tile. It seems like Card Hunter uses such large units in older screenshots of the game (might just be mock-ups), but I’m not able to find a gameplay video showing it in action. In all videos I can find, large units take up 22 tiles.
Descent and some editions of D&D are board games/pnp rpg’s that use asymmetrically large units, but they can leverage the processing power of the human brain to figure things out from a simple set of rules.