Last week we considered the basics of being mounted and of mounted movement. This week, we'll consider mounted combat.
Attacks of Opportunity While Mounted
Being mounted usually doesn't affect your ability to make attacks of opportunity. If your mount is capable of attacking, it can make attacks of opportunity while you're aboard. If, during your turn, you've succeeded on a Ride check to fight along with your mount (see the section on trained war mounts), both you and your mount can make attacks of opportunity during the current turn. If you both threaten the same space or creature, you can even both make attacks of opportunity against the same target. If you have not succeeded on this Ride check, then either you or your mount can make attacks of opportunity this turn, but not both. You don't have to decide which one of you will make attacks of opportunity until one of you gets a chance to make an attack of opportunity.
When you and our mount move, you both are subject to attacks of opportunity from your foes (your mount might be the one actually doing the moving, but you're moving as well). For example, when you and your mount leave a threatened space, you both provoke attacks of opportunity from foes that threaten that space. A foe who can make multiple attacks of opportunity in a round (for example, a foe with a high Dexterity score and the Combat Reflexes feat) can make an attack of opportunity against you and one against your mount.
As an optional rule, you might want to treat a rider and a trained war mount (or a special mount, such as a paladin's warhorse) as a single creature in battle. When the pair moves, they provoke one attack of opportunity for each foe that threatens them, not one each.
Trained Mounts in a Battle
When a mount has an Intelligence score of 2 or less and it has been specially trained for combat riding (see the Handle Animal skill description), you'll find that it is quite an asset in battle. Thanks to the mount's training, you and it function more or less as a single unit in combat, and you gain all the benefits noted in the Basics of Being Mounted section. You must succeed on Ride checks to get the full benefit of your mount, as noted in the Ride skill description and summarized below:
Fight Along with Your Mount: Make a DC 10 Ride check as a free action. If you succeed, you can direct your mount to attack a foe and you also can attack as well. See the section on attacking while mounted for details. If you fail this check, or don't bother to make it, either you or your mount can attack this turn, but not both of you.
Get Cover from Your Mount: Because you and your mount share a space on the battlefield, you normally cannot claim cover from your mount. Whenever someone attacks you, however, you can attempt a DC 15 Ride check to claim cover from your mount. If you succeed, you get the benefit of cover (+4 to AC). According to the D&D FAQ, the cover benefit applies to all attacks made against you during the same place in the initiative order. If foes attack you several different times during a round, you must make a new Ride check to get cover from your mount against those attacks. You cannot claim cover while you're casting a spell or making any kind of attack.
Using your mount for cover isn't an action, and you can do so anytime you're attacked (subject to the limits noted previously). The rules don't say so, but using your mount for cover represents you actively avoiding attacks, and it's reasonable to assume that you cannot do so when you are denied your Dexterity bonus (if any) to Armor Class.
Guide the Mount with Your Knees:You make a DC 5 Ride check at the beginning of your turn. If you succeed, you don't have to use your hands to control your mount until the beginning of your next turn, when you have to repeat the check to continue guiding your mount with your knees. Although the Ride skill description doesn't specifically say so, guiding a mount with your knees is not an action at all.
Mount or Dismount Quickly: A successful DC 20 Ride check allows you to get on or off a mount one size bigger than you as a free action, but you must still have a move action available to you this round to do so. The Ride check for a fast mount or dismount is subject to any check penalty you have for armor or for carrying a load. If you fail the check, you still get on or off your mount, but you use a move action to do so. (This is why you must have a move action available to you to attempt a fast mount or dismount.)
If your mount makes a single move, you can perform a fast mount or dismount either before or after your mount moves. If your mount runs or makes a double move, you'll have to get on or off while the mount is moving. The rules don't say if the DC for a fast mount or dismount assumes that the mount is stationary, but it's a good bet that they do. Add +5 to the DC for fast mounting or dismounting a moving mount. You perform the fast mount or dismount when your mount has completed half its movement for the turn.
Soft Fall: If you fall off your mount, you can succeed on a DC 15 Ride check to avoid damage from the fall (see Part One for details).
Stay in the Saddle:Any sudden movement your mount makes can make you fall off, and you can be knocked off your mount whenever you take damage. Make a DC 5 Ride check whenever either event occurs. If you fail the check, you fall off your mount.
You might have to make this check several times during a round. Staying in the saddle doesn't require an action.
Unruly Mounts in a Battle
When a mount has an Intelligence score of 2 or less and it has not been specially trained for combat riding (see the Handle Animal skill description), it can prove a detriment in battle.
Most mounts that aren't battle trained also aren't aggressive and would prefer to flee from danger. A regular camel, horse, mule, or pony is a good example. Adventurers may find it easier to simply get off such a mount and fight on foot.
If you want to stay mounted and still fight, you can try to do so, but it takes effort. To keep control of the mount, you must succeed on a DC 20 Ride check as a move action that provokes an attack of opportunity. With a successful Ride check, you can direct your mount to move, stand still, or do anything else it normally could do while carrying a rider. If you decide to make the mount move, your check to control it and the mount's movement are part of the same action, but you've still used up a move action during your turn. You can perform a standard action during the round, either before the mount moves or after.
If your check fails, the mount does what it will. Your uncontrolled mount most likely uses the withdraw action to make a double move away from danger. Doing so prevents attacks of opportunity against the mount when it leaves its first space, but not when it leaves other spaces where foes threaten it (see page 143 in the Player's Handbook). Because you and your mount move as one, you reasonably can assume that you involuntarily withdraw as well and that you also get the benefit of the withdraw action. Your frightened mount also might break into a run, which would leave it and you subject to attacks of opportunity from the first space the pair of you leave.
If you keep your mount from panicking, you can perform most of the tasks discussed in the section on trained mounts. Most herbivores will not fight unless trained for combat riding, and it is pointless to try to fight along with such a mount.
Aggressive Mounts in a Battle
A character could ride a mount that isn't cowardly in battle, but still isn't trained to carry a rider into combat. For example, a riding dog might be inclined to fight when danger threatens. If you're a druid or ranger, you might use your wild empathy ability (and maybe a speak with animalsspell or two) to induce some big carnivore to give you a lift. If you find yourself in a battle while still astride your mount/ally, you and your improvised mount still act on your initiative number. You must attempt a Ride check to direct the mount's actions, which is noted in the section on unruly mounts. If you fail, the mount might stick around to fight. If so, the mount moves where it will, but you still can't take any other action in the same round that you made the failed check (you spend your time just staying on).
Some Unofficial Optional Rules
These rules might come in handy when something unusual comes up.
Bailing Out: If you fail to control an untrained mount, you don't want your frightened mount to gallop away from a battle with you hanging on for dear life, so you can use a free action to just let go and fall off your mount. Your turn is still over, but at least you're still in the action. Deliberately falling off your mount is a free action for you. If you decide to fall off, you can make a Ride check to soften the fall (which doesn't take an action).
Riding Along with an Aggressive Mount: If your mount isn't trained for war but chooses to fight with you aboard, you can just give the mount its head. You and your mount make separate initiative rolls. Because there are some full-round actions you cannot perform while your mount moves (see Parts Three and Four), you must delay until after your mount's turn to use such actions if your mount's turn in the initiative order comes before your own turn comes. Even then your mount's movements could keep you from performing your intended action.
When it's finally your turn to act, you must succeed on a DC 10 Ride check to adjust your actions to fit your mount's uncontrolled movements. The check is a move action for you, but it does not provoke attacks of opportunity. (You're looking after yourself, not your mount.) If you fail, your mount's movements keep you from taking any actions this round. If you succeed, you can use a standard action. Just remember that you're allowing your mount to take you where it will, so your options might prove limited.
That's all the time we have this week. Next week, we'll consider just what you can do while your mount moves.
About the Author
Skip Williams keeps busy with freelance projects for several different game companies and was the Sage of Dragon Magazine for many years. Skip is a co-designer of the D&D 3rd Edition game and the chief architect of the Monster Manual. When not devising swift and cruel deaths for player characters, Skip putters in his kitchen or garden (rabbits and deer are not Skip's friends) or works on repairing and improving the century-old farmhouse that he shares with his wife, Penny, and a growing menagerie of pets.