Ultra-simple mass combat KISS 5 or 5.5

Ultra-simple mass combat, inspired by Green Ronin in D&D 3

1 Command tool (tool: banner – see my commander post)

Action
Range: 3 m
aid or morale support roll: +2 fear, charm, or morale (mass combat)

Commander level (army)

aid for Proficiency Modifier –1 units

No need for additional skills. Alone or with tool, or nothing if magically your PC is versed in strategy.
The skill is useful to prepare the field to gain an advantage, but it's outside combat, like any good tool!

MASS COMBAT KISS – Keep it Simple Stupid
PRINCIPLE
Unit = creature
Dungeons & Dragons 5th Edition rules unchanged
Feats + WM used as-is
Commander = activation
1 WM or feat / unit / round

COMMANDERS
Unit commander

Bonus action (3 m):

activates 1 WM or feat

Strategic commander

Action:

activates PB – 1 units, aid (advantage or +2 to saves)

Without commander
disadvantage 1 round, then replacement or healing

WEAPON MASTERY (OFFICIAL 2024)

Cleave (greataxe, greatsword) → hits a 2nd nearby target
Graze (heavy weapon) → damage even on a miss
Nick (dagger, shortsword) → extra quick attack
Push (hammer, shield, spear) → pushes back
Sap (mace, club) → target has disadvantage
Slow (longbow, whip) → reduces speed
Topple (warhammer, mace) → knocks prone
Vex (rapier, longsword) → advantage on next attack
Flex (versatile weapon: bastard sword, spear) → improved damage

FEATS (UNCHANGED 2014 or 2024 if you want)
Sharpshooter → ignores cover + high damage
Sentinel → stops movement
Polearm Master → engagement control
Charger → bonus after movement
Shield Master → area defense
GWM → heavy strike
Crossbow Expert → ranged attack in melee

CANTRIPS = MAGICAL WM
Fire Bolt → damage (1 unit)
Ray of Frost → damage + Slow
Shocking Grasp → no reaction (Sap)
Minor Illusion → tactical advantage (Vex)
Mage Hand → light push / sabotage

“HEALING”
Healer (unit or PC)

Action or bonus action: heals a unit (abstract value)
removes disadvantage, WM effects (Sap, Slow, etc.)

Options – depending on spells or non-magical healing
Light care → removes penalties
Healing → restores significant HP
Rally → cancels disorganization, cancels rout, etc.

Limits
1 heal / unit / round

PLAYER ROLES

Commander
activates WM / feats
multiplies effectiveness

Healer
keeps units active
cancels enemy effects

Caster
spells = major effects
cantrips = damage, magical WM

Fighter
duel
eliminates key targets

Infiltrator
kills commander
sabotage

MEDIEVAL UNITS
Infantry → Vex / Sap
Heavy infantry → Topple / Sap
Archers → Slow / Vex
Cavalry → Push / Topple
Pikemen → Push / Polearm Master

MONSTERS
Wolves → Topple
Orcs → Vex
Undead → Graze
Trolls → Cleave
Dragons → Push / Sap

ELITE UNITS (premium monsters from the MM)
1 intrinsic feat
usable without commander (1/round)

Examples:

Archer → Sharpshooter
Rider → Charger
Pikeman → Polearm Master
Guard → Sentinel

MISSIONS (RP)
kill commander → cuts WM
capture → advantage
sabotage → enemy disadvantage

SCALES 1 round =
6 sec → tactical
1 min → urban
30 min → engagement
1–6 h → battle
1 day → war

SUMMARY
Official WM + associated weapons
feats unchanged
command = activation
simple integrated healing
clear roles (commander, healer, mage)

For the extra options, paste and ask chatGPT! 

It sounds like a fun way to scale up battles. Do players control these units or is this DM facing to calculate how a battle goes while the PCs are doing their thing?

simple!  It depends, like any normal combat with NPC. Players can always control allies NPC. Table's and DM choice.

 here is my disclaimer:

Commander Player Profile
The commander role is intended for a player who enjoys planning, coordinating, and making quick tactical decisions.

This player:
- manages allied units (may have a unit commander “companion” or play one directly)
- uses the Help action on multiple units
- chooses simple effects (assault, defense, movement, pressure)

This role requires more attention than the others, but does not involve additional complex rules.

🪶 📜 Simplified Commander Version (beginner)
Simplified commander.

Instead of choosing an effect, each helped unit only gains advantage on its next attack.

The commander makes no other choices.

others plays NORMALLY (duels, sabotage, assassination, with 6 sec rounds to get a RP bonus) 

and/or casting spells - same damage/effets, scaled time/distance!  Healing. Just pretend your spell is a special ritual for mass combat! dnd is not realistic!

A 8d6 fireball affects a unit x100 warriors , so a round x100 time, x100 distance, x100 incantion time, x100 area of effet etc!

Projet collaboratif - Forum AideDD  just translate!

or paste it, ask friend chatgpt to add supression fire, false retreat, adding feats thatt work with/without this syste, etc,  or use my own work. Since it is 100% dnd 5 based, it is easy for AI to modelize!