Variant Initiative System: Phase Initiative

Phase Initiative

This mechanic has been adjusted from another RPG called Pythos. In phase initiative, rounds and turns are resolved in phases, which define when during a round a specific type of action taken during a character's turn happens. All who perform a type of action resolve the action "simultaneously" during the appropriate phase of the round. Turns taken during the same phase resolve "simultaneously"; this means one's actions do not occur before another's, unless those actions occur in a different phase.

NOTE: Please note that some house rule options outside the scope of this house rule are accounted for in this topic. These are primarily contained within the sections labeled “Which actions are available?”.

Phases

The phases follow in a specific order for resolution. Rounds begin with the Dungeon Master declaring what NPCs will do, either in groups or individually, and with players declaring what they will do simultaneously. Once their actions are chosen, they describe what they plan to do. A player may stop their turn's action before it is resolved, but not may not replace it with a new action until the next round.

Order of Phases

* Declare & Describe * Passive Phase: Beginning of Turn/Round * Defense Phase * Action Phase * Utility Phase * Passive Phase: End of Turn/Round

Turn Order

Turns of a phase are resolved in the following order. If the PCs have managed to Surprise their Enemies, the PCs go before the Enemy NPCs for the first round.
  • Enemy NPCs
  • Allied NPCs
  • PCs

Initiative Bonus

In some cases, the DM or the players may need to resolve an action based on who in fact would go first in a turn sequence. Characters should perform an initiative contest. The higher result determines who has initiative for that contest and that contest alone. An initiative contest does not in any way set a character's initiative for the round.

Declaration & Description

At the beginning of a round, players and the DM choose their actions simultaneously rather than in a specific order. These declarations describe a character's intent for the round. A countdown should be given and at the end, each player lays down something on the table specifying their action. For this purpose, a player should have four tokens describing the general action they plan to do. Players choose their actions from one of four options: Defense, Attack, Utility, and/or Move. Once all actions have been declared, players describe their intended actions based on available mechanics and roleplay for those at the table and the DM.

Movement

In D&D 5e, movement speed can be broken up between a player's move action and action. If a character chooses the Defense, Attack, or Utility Phase, they can move up to their movement speed during this turn, but subtract the value from the respective value when initiating the Move Phase. Every player may move during the Move Phase. If they have no movement left, their only option is to drop prone.

Start of Turn Passive Phase

Before any turns are resolved, any effects or qualities which begin at or last until the start of a character's turn are handled here.

Defense Phase

The player chooses to defend himself against something. He moves or prepares himself to try and stop attacks, get the high ground, or the like.

Which actions are available?

Dash, Disengage, Dodge, Escape, Help, Hide, Ready

Ready

A character that readies an action initiates the chosen response regardless of the phase, instead acting when the triggering event occurs as a Reaction.

Attack Phase

The player chooses to attack something on his turn. He swings his sword, grapples, or performs some kind of maneuver.

Which actions are available?

Aim, Attack, Charge

Simultaneous Resolution and Damage

As a sample scenario explaining how "simultaneous" resolution occurs in this system, the Attack action is bound to be a point of conflict. This is how the mechanics operate. Since Attack actions are resolved "simultaneously", if a PC and an NPC take the Attack action in the same round and target each other, both of them attack "simultaneously". Thus since NPCs resolve their Attack actions first, even if they drop a PC to 0 HP, the PC still takes their Attack action that round (potentially allowing them to drop their foe to 0 HP as well), unless they choose to cancel their Attack action upon seeing their HP drop to 0, at which point they cannot take any other action that turn; during the End of Turn Passive Phase, the PC with 0 HP would drop unconscious and begin dying.

Utility Phase

The player chooses to do something other than defend or attack. The player might look for something, disarm a trap, or perform a special action.

Which actions are available?

Drink Potion, Equip Shield, Feint, Goad, Menace, Parley, Search, Stabilize Dying Creature, Use an Object

Move Phase

The player chooses to move. In general, players who choose to only use Move can also use Dash, but would use this first part of their movement during the Defense Phase. Players who moved during the Attack Phase can utilize the remainder

Which actions are available?

Move, Overrun, Sprint*, Tumble

Sprint

New Action: A player who chooses not to Dash during the Defense Phase (or use an ability during the Utility Phase) can choose instead to Sprint during the Move Phase. The player can move up to three times their move speed in a straight line, but not through difficult terrain.

End of Turn Passive Phase

Before a round finishes, any effects or qualities which begin at or last until the end of a character's turn are handled here.

Bonus Actions

A player who can perform a Bonus Action performs the type of action during its specified phase.

Reactions

A reaction can be taken whenever it would normally be triggered, such as an opportunity attack if the player moves with the Dash action in the Defense phase or with their Move action during the Move Phase.

Free Actions

Free actions can be taken regularly, though some may only be able to be taken during a specific phase depending on what the free action is trying to do.

Spells, Magic Items, and Class Abilities

Spells and activating magic items or class abilities are cast and activated as normal, but their effects are resolved during the phase which best applies to a spell's intended use. Spells which take a longer time to cast are completed in the following turn or at the end of the casting duration during the phase which best applies to a spell's intended use.

Would you be able to provide a concise, numbered list of phases and turns and such? I got a bit lost reading through this and am struggling to visualize the flow of a combat round.

Added it to the main post. Done!