Mounted Combat Rules
Mounted combat in Dungeons & Dragons 5th Edition gives players a genuinely useful tactical option — faster movement, elevated positioning, and the synergy of two combatants sharing a turn — but it comes wrapped in a ruleset that trips up tables more often than almost any other subsystem. The rules appear in the Player's Handbook (PHB, p. 198) under a deceptively short entry that leaves significant gaps for Dungeon Masters to interpret. Understanding exactly what the rules say, and where they stop saying anything, is the foundation of running mounted encounters without a mid-session argument derailing the whole thing.
Definition and scope
A mount, in 5e terms, is any willing creature that is at least one size category larger than the rider and has the appropriate anatomy to carry one. That last qualifier — "appropriate anatomy" — is left to DM discretion. A horse qualifies obviously. A giant spider technically fits the size requirement for a Small rider, and the PHB does not prohibit it.
The mounted combat rules govern two distinct situations: controlled mounts and independent mounts. A controlled mount acts on the rider's initiative count, not its own, and can only take the Dash, Disengage, or Dodge action on its turn. An independent mount keeps its own initiative and can take any action its stat block permits — it acts as a separate creature in the initiative order. Most trained warhorses default to controlled behavior; a wild or sapient creature the rider is persuading rather than commanding typically behaves independently.
The scope is deliberately narrow. Mounted combat rules handle initiative sharing, attack targeting, and falling. Everything else — flanking from a mount, how height affects ranged attacks, whether a dragon counts as a valid mount for a Medium character — falls into the broader rules framework or DM adjudication territory.
How it works
Mounting and dismounting each costs movement equal to half the rider's speed. A character with 30 feet of movement spends 15 feet to mount and still has 15 feet remaining — or can split that movement before and after mounting.
When a controlled mount moves, the rider moves with it without spending the rider's own movement. The rider still takes their own action and bonus action normally. Think of the mount as a vehicle that also gets to attack, in some configurations.
Combat targeting follows a clear rule: if an attack would knock the mount prone, succeed on a Concentration check (DC 10 or half damage, whichever is higher), or otherwise drop the mount, the rider makes a DC 10 Dexterity saving throw. Success means a controlled dismount to an unoccupied space within 5 feet. Failure means the rider falls prone in that same space — which in a crowded encounter is its own special problem.
Melee attacks against the rider can target either the rider or the mount. There is no rule forcing enemies to attack the mount first. A goblin cavalry unit trying to unhorse a paladin will rationally target the warhorse at lower AC, while a more tactical opponent might go straight for the rider. Both are valid.
Common scenarios
Charging through difficult terrain. A controlled mount uses the rider's initiative and is subject to normal difficult terrain rules — movement costs double. A warhorse crossing rubble or mud is not immune to terrain simply because it has four legs and barding.
The rider attacks, the mount attacks. On a controlled mount's turn, the rider takes their full action (including Extra Attack if applicable) and the mount takes one of its three permitted actions. A paladin on a warhorse can cast Divine Smite, take two attacks, and the horse can still Dash — but the horse cannot also make a Hooves attack, because Hooves is not Dash, Disengage, or Dodge.
An independent mount charges into combat. Here the mount acts on its own initiative, takes any action its stat block allows — including Multiattack if it has one — and the rider acts separately on their own turn. The rider is essentially a passenger with agency. This arrangement is more powerful but less predictable, and it interacts differently with spells like Command or abilities that control the rider or mount specifically.
Falling unconscious mid-ride. If a rider drops to 0 hit points while mounted, they immediately fall off. No saving throw. The PHB (p. 198) treats this as falling from the mount's space, landing prone. A mount with 40 feet of movement that happens to be 15 feet in the air on a stone bridge when this happens has real consequences.
Decision boundaries
The mounted combat rules have three genuine gray zones that come up repeatedly at real tables.
- Can a flying mount hover while the rider casts a concentration spell? The rules don't prohibit it, but a flying mount with a hover speed must be specified in its stat block (like the Pegasus, which lists hover: no). Without hover, losing concentration might trigger the mounted fall rules at altitude.
- Does the Cavalier fighter's Unwavering Mark apply while mounted? The Cavalier subclass from Xanathar's Guide to Everything (p. 30) is built around mounted combat, but its features interact with the base mounted rules without always clarifying conflicts — a DM call is often required.
- Size category edge cases. A Medium character cannot ride a Medium creature by default. This is a hard rule. But a Small character (gnome, halfling) can ride a Medium creature, which opens up companions, summons, and unusual mounts that Medium characters simply cannot access.
For a fuller picture of how edge cases like these connect to the game's broader rule structure, or to find answers to specific table disputes, the FAQ addresses the most common mounted combat questions that arise in actual play. The main rules reference provides the surrounding context for how mounted combat fits within the action economy and encounter design as a whole.