The following content represents a (hopefully not misguided) attempt to complicate and deepen the combat in Shadowdark RPG, adding more tacticle elements to the game, and encouraging dynamic movement and use of terrain. The material is, at time of writing, almost entirely untested—at least within this particular game. Here I can give only the first draft of rules, which I intend on trying in my upcoming sessions, and I will publish here further iterations. Lastly, I would note that a substantial portion of these rules are adapted from the system Dynamic Combat Movement by Raven Tear Productions.
During combat, each faction acts on a single turn. The players may therefor decide to act in whichever order they see fit, whilst the monsters (along with any additional factions) act in such lumps during the referee's turn. Initiative—that is whether the players or referee act first—is to be decided with 50/50 odds normally, though factors such as surprise or habitat may modify this element.
Each character may take one action on their turn, and move up to their speed. An action can be to attack or cast a spell, though it can also be some other interaction, such as kicking over a table or tossing sand in a foe's eyes. Further, each character is afforded one reaction per round, which they may use to take certain actions on their foes' turns.
When one character enters a space within melee range of another, they may be interrupted. A character may interrupt another by using their reaction to make a charisma check against the mobile character's Dexterity score. On a success, the interrupted character cannot exit melee range of the character interrupting them on this turn.
Exiting a character's melee range provokes no interruption from them, and any character may further use their action so as to provoke no interruptions during their movement.
A character standing still is an easier mark for missile attacks than one on the move. If a character has not moved on their most recent turn, ranged attacks against them are made with advantage.
When a defendant is beset by at least two assailants on opposite sides, all melee attacks made against them have +2 to hit.
When an assailant is standing at a substantial hight above their defendant, they may make melee attacks with advantage.
When a character hits another with a melee attack, the assailant may choose to advance on the defendant, pushing them into a space to their immediate rear. The assailant must then move one space, such that they are still within melee range of the pushed character. If the defendant is pushed into a wall (or any other obstruction) they must save or fall prone. If the defendant is pushed off of a ledge, they must save or fall below (on a success they are left dangling by the hand).
A defendant may attempt to halt an advance if they a) are notably larger than their assailant, b) are brandishing a shield, or c) use their reaction. If they attempt so to do, they must pass a Strength or Dexterity check against a DC of 10+ the attack's to hit modifier.
If a character uses their action to impose disadvantage on attacks against them, and is still hit, they may choose which space behind them to move to when advanced upon.
When a defendant is missed by an assailant's melee attack, they may slip into any unoccupied space within 5', and the assailant must move into the defendant's previous space (or one space toward it, in the case of attacks made with reach).
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