I can't really get into Mike's or TFMurphy's head so the best I can do is speculate. There are basically two situations when new commands are added:
1. The official hold needs it
2. A public feature request
As you can see there is no case "
let's sit down and thing thoroughly what kind of command we want to add"
. Don't get the wrong impression that no one thinks about those things, but the way commands are usually implemented are in the context of their origin.
If we needed a command to attack specific tile then we add a command to attack a specific tile, not a rectangle of tiles.
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The additional reason for Game Effect is that in the game you generally don't have effects appearing over a huge space (bomb explosion being an exception) so that's that.
As for Attack Tile there is no good reason other than the general way the commands are added. Also, I guess, that with the exception of bombs there aren't any things in the game which "
attack"
multiple tiles at once so it's more intuitive for the command to attack a single tile.
Which is pretty much the same argument as for Game Effect.
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