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DM of the Rings XXXVIII:
As Simple as Calculus

By Shamus
on Wednesday Dec 6, 2006
Filed under:
DM of the Rings


Aragorn, Legolas, Gimli, Lots of Orcs, Grapple Rules, Attack of Opportunity
Aragorn, Legolas, Gimli, Lots of Orcs, Grapple Rules, Attack of Opportunity

And here I finally deliver the joke / point I wanted to make way back in strip #16. The rules as presented in the rulebook seem sensible enough: If someone enters a square adjacent to an enemy, that enemy gets a free swing at them, right then and there, regardless of who’s turn it is. I’m sure proponents of the system can give you a nice list of reasons for this, why it makes combat more realistic, or what exploit it is supposed to counter.

On the surface this makes sense, although there are so many exceptions and qualifiers and footnotes and special cases that three pages after you’ve read this simple premise you’re knee-deep in a dark coagulating pool of madness. Aside from the complications of suddenly inserting a turn out of established order, there are rules to check and bonues to apply and – most sadistic of all – more information to track. Now you have to track who’s taken an AOO this round and who hasn’t, and how many such attacks each combatant is allowed, and how to handle cases where two people get AOO at once, or what happens when one AOO knocks the target into an adjacent square and creates another AOO, or how to handle AOO between creatures of greatly differing sizes and how to deal with tentacled foes and how all of this intersects with rushing, sprinting, and grappling, or what to do if an AOO is possible but the potential attacker might not be aware of the target and does this apply to non-combatants and SWEET MERCY WHAT IS WRONG WITH YOU PEOPLE!??! WILL YOU LOOK AT ALL THIS PAPERWORK!

Comments (150)

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  1. Rose says:

    lol, I love the end of this one. I’d say screw it and let Legolas nail the guy regardless, but I don’t know the rules to begin with so. . . *shrugs*

    • Elfguy says:

      Well the DM got it backwards anyway…you don’t get an AOO for someone ENTERING a threatened square, you get one if they LEAVE a threatened square without using a 5 foot step or a “withdraw” action.

      And unless Lego has some feat that lets him AOO with a ranged weapon, he can’t do it even then.

  2. Lev says:

    AoO: You take it when you leave a threatened square or do an action that provokes one.

    There. Was that so hard?

  3. Techan says:

    Within my gaming group, we simplify the AoO to this

    There are many actions that provoke attacks of opportunity, there is a table in 3.5 that outlines this pretty well. (examples: shooting a ranged weapon, casting a spell, or drinking a potion all while engaged in melee)

    Now the real question is WHEN can you take this attack of opportunity, and when can’t you?

    I don’t know if it’s exactly on par with the official rules, but we play it as such:
    If you are NOT engaged in combat with anyone other than the enemy who is provoking the attack of opportunity you can take it. You get ONE attack of opportunity per round unless you have a feat that says otherwise. If you’re engaged with two or more enemies (and they’re engaged with you, i.e. their attention is on you and you didn’t sneak up behind them or anything), both in threatened squares and one of them does something that would normally provoke an attack of opportunity, you can’t take it. The other enemy there would hold your attention and prevent you.
    This doesn’t necessarily apply to enemies who just happen to be next to you, for example, if you and another PC are fighting side by side, each with an orc in front of you, you are both considered to be in one on one combat and therefore if the orc you’re fighting provokes an attack of opportunity you can take it because the other orc near you is engaged with your teammate, his attention is held by the PC trying to kill him so he’s not tying you down.

    It seems the two most commonly used AoO provokers that come up are the entering and leaving a threatened square. Charging into battle with someone does not provoke an attack of opportunity in our games, it seems stupid to us. Withdrawing, though, does, and it tends to be the one that comes up most often. As per the rules above if an attack of opportunity would normally be provoked by someone leaving a threatened square, the person disengaging may make a tumble check, which if successful, negates the attack. To keep people from abusing this we make it such that if you roll a critical fail to tumble away, not only do you fail to avoid the attack, but the attack auto-crits, cause you fell on your ass and made an easy target.

    Essentially it boils down to just making sure the PCs and the DM specify (in melee) who they are currently engaging. In a case of 1 on 1, attacks of opportunity work as normal, take one whenever it’s provoked (as per the table of actions and 1 per round rule). If there’s another enemy engaging you aside from the one provoking the AoO, you cannot take it.
    A bit simpler than the book’s descriptions I think and it makes sense, to us anyways.

  4. hopeless says:

    So if Lego has Combat Reflexes wouldn’t that make this a moot point?

    Oh yes the dm’s not handing out xp…

    Been wondering what would have happened if one page dealt with them gaining a level…

    Where would it have happened?



    What do you think?

  5. subzero21601 says:

    I’ve been in this situation multiple times when one of my players, (I’m DM) thought that a passive feat was the same thing as an attack. He was a fighter and would rush in the fight saying “I attack the -insert opponent- and use Great Cleave” and my response every time was “It’s Passive and is only usable under a given circumstance! keep on trying to use it as an attack you’re character will “forget” how to swing a sword with that much force.”

  6. shoggo says:

    this ist the point that has my group bugged for a long time tille we sat together and discussed it and come to this
    1vs1 – all rules in the book
    1vs many – the % rule / you take a 10sider androll how good you nail him, in return he rolls how good he doges/escapes… the difference is the % of damage you roll 80 he rolls 40 you do 40% damage of a 10d6 roll
    many vs many – the rule of cool / mostly the ini gets split up at how detailed you can tell how you kill your enemy (lame if you have a dagger/awesome if you poke out his eyes and crush his head with the helmet on ^^)

  7. […] of geeks sit down around a table and play Dungeons & Dragons. It starts here, but frankly, episode number thirty-seven (and it’s just caught up with the end of the first film) is the best summary of why many find […]

  8. anndreana says:

    i fell that you are doing a good job with being a dm but yo should work on the story a little. i know you are trying to stick to the movie but have them get attacked a little bit more and find treasure more. also, if they go against the plot, blow them up, that’s what happens when i tried to KILL the dm last time i played this.

  9. […] I found something hilarious must read for fun DM of the Rings XXXVIII:As Simple as Calculus – Twenty Sided […]

  10. WJS says:

    I like the comments that say “We don’t use AoOs, but I agree you shouldn’t just be able to dash through a gang of orcs with impunity”. So… what do you do? If you simply don’t let players do that, then a couple of men can block a passage the size of a freeway. This is clearly just as ridiculous as letting them run straight through. So you let them have a free attack? Guess what genius: That’s what an AoO is!

    AoOs address a major problem with turn-based combat, in that without them characters will just stand there like idiots while the guy next to them aims a bow at them, or casts a spell, or fumbles around looking for a potion, or any of a thousand other things that a guy with a sword should not suffer idly. Is that really a difficult concept to grasp for some people?

    Sorry if this sounds harsh, but I find it quite irritating that so many people seem to implicitly agree with the concept of AoOs, but go ahead and attack them anyway. Do they just not like the name or something?

  11. Von says:

    Is there a program which can calculate these sorts of combat odds, accounting for rules and order of engagement and such, to free up DMs and players for story-crafting and action?

  12. MaxForrest says:

    I usually make sure not to let my friends get into grapples when I’m dming. Too many rules.

  13. 4ier says:

    There are a couple of messed up character encodings in the comments.
    don't should be don’t
    shouldn't should be shouldn’t

    PAGE 2
    Blue sky at night:
    Shadowrun's should be Shadowrun’s

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2 Trackbacks

  1. By The DM Of The Rings » Get Writing, Rob Farquhar! on Saturday Aug 20, 2011 at 7:54 pm

    […] of geeks sit down around a table and play Dungeons & Dragons. It starts here, but frankly, episode number thirty-seven (and it’s just caught up with the end of the first film) is the best summary of why many find […]

  2. By DND Pathfinder 3.5 RP - FTP-Anime Forums on Tuesday Jul 17, 2012 at 8:47 pm

    […] I found something hilarious must read for fun DM of the Rings XXXVIII:As Simple as Calculus – Twenty Sided […]

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