Okay, I'm not fully sure this hasn't been proposed before, but I didn't find anything with some obvious search terms. I also know with TSS coming out soon, this isn't a good time to propose new features as they won't make it in there no matter how good.
But not minding that, I just want to write it out in case it inspires someone at some point. I think it's more of something that could be developed to be a great idea with a few good tweaks as something I already consider great.
How to implement a monster that splits into two when you strike a lethal blow? As far as I know, this has only been suggested for snake-type monsters, and not single-square ones. Let's see.
If splitting a monster can spawn the new monsters next to you, these should not kill you on their very next turn. Therefore, they should skip one turn. Let's call this the stunning rule. New monsters are stunned and lose one turn after being created by splitting.
The monsters should not be able to be split without limit, as that kind of defeats the goal of clearing a room. I suggest having three sizes of splittable monsters, such as large, medium and small. Small monsters don't split any further, but die normally when slain. (I have another idea I'll touch on below. It's probablyy needlessly complex.)
Now, these monsters might be related to tarstuff somehow, so I am going to name the one I am proposing here Green Jelly. I didn't invent different mechanics for other colors, so let's just assume it's possible to grow Gel in very special ways and use special materials to make it behave differently and create Jelly monsters. And that's why they are green. Are there Red or Blue Jellies? I don't know.
GJs can be large, medium or small. If you kill a large GJ, it splits into two medium ones. Medium ones become small and small ones just die normally. They would move like Gel Babies for consistency, unless people feel the monsters would be more interesting with other kind of movement pattern. Testing would be useful to find this out.
After being slain, the new, stunned GJs need to be placed somewhere nearby. If you pick two standard positions relative to the player and his sword, these spots might not always be open. So, a rule to find secondary spots for them can be employed.
I propose a 90-degree rule for the initial split positions. That is, the two new monsters end up in 90-degree position relative to your sword, one to the right and one to the left. The two basic results are that if you stab a GJ right above you, one part ends up diagonally left and up, and one right and up. If you stab one diagonally right up, one ends up two squares above you, and one two squares right. Symmetry takes care of other positions.
In other words, you end up with a T-shape, with you being the leg and the sword being in the center, and the new monsters the arms.
Now, these are the first position that are tried, but if they are blocked, the new monsters will end up in other places if possible. To break the tie, we try to find the place for the one on the left side first. If it can't go on its ideal position, we try all the position in counterclockwise order around the sword starting from the ideal one until there is an empty one. (This means that if there are multiple open positions, it'll probably end up farther from you than nearer.)
Obviously it cannot spawn on the player and kill him, 'cause that would be super unfair. If there is no spot, then it never spawns at all and you just killed the original monster. If it can spawn, the same procedure in reverse is used for the right-side GJ. Thus, in cramped positions you might avoid one or even both new monsters being spawned.
Note that the resulting monsters should always end up on a square next to the sword. Which I think makes the most sense.
Splitting can be treated as the new monster moving from the position of the old one into the new empty spot, if such can be found and the move would be normally legal. After moving, a new monster will skip its next turn due to being stunned.
Splittable monsters at the very edge of explosion could split too and the resulting monsters pushed outside the explosion's area if possible. This needs a specific rule too, but I'm just leaving this idea out there for now. Other ways of killing monsters would have to be dealt too, but I feel like one getting eaten would just end up with it being, well, eaten. And gone.
A possibility is to allow the GJs to merge too. This would work so that if a monster moves during its turn onto another monster of the same kind and size, they combine to form a larger one, unless both are already large/maximum size. This merging could happen right after being split into two, in which case the resulting merged monster would be stunned. If it happens as a result of a normal move, then the resulting monster should not get to move anymore during the same turn.
Now, there is another option for more monster sizes. I'm not happy with this idea, as it could not be clearly indicated by the graphics alone. Instead of three sizes, the monsters have a hit point total. Every time one is hit, the game subtracts one hit point from it if the total is odd, or two if it is even. The resulting hit points, if positive, are divided by two to give the totals for the newly split monsters. If the result is zero, the monster dies.
Any monsters can combine with the same type by adding their hit points together until this rule, so it does have some merit at least. However, I feel it is a bit too complex to be fun.
That's it. Now, if anyone remembers this idea being discussed before, let me know. I'll link to the old discussion, or even remove this post if it's all been hashed out. I just put this out here in case it inspires someone to create an interesting adversary in some game or other. (Doesn't have to be DROD. I was just thinking DROD when I came up with this.)
