Final Fantasy 14 has a combat subsystem called "battle regimen." In battle, when in a party with other players, you can all activate a battle regimen. Each of you chooses an action from your usual set of actions - attack, cast a spell, etc. Then someone tells the regimen that it is complete. The regimen then goes off - automated -each of you doing your thing in the order you planned them in. If you all hit, you get a bonus result. There are various bonus results based on the combinations you made. For example, two regular attacks puts a defense-down debuff on the target.
Now this is a fine system, as it lets players team up to get more out of their actions than they could alone. The problem I have with it, is that it replaces one of the most amazing MMO inventions of all time: skillchains. FFXI, the previous Final Fantasy MMO, had a similar system that allowed players to connect their special "weaponskill" attacks for bonus effects.
Weaponskills are special attacks that you can perform when you have enough TP (tactical points, I think). You gain TP when you deal physical damage to an enemy or are dealt physical damage by an enemy (not with spells). When you have sufficient TP you can use it to execute a special attack of your choice from those your character knows. This system got its start with limit breaks, way back in FFVI (and made famous by FFVII). Both XI and XIV use weaponskills with very similar systems. Note that gaining TP when you attack and when you are hit is important. On attack you feel like you're building up toward something more exciting than just endless basic attacks. The when-hit component helps you comeback against an enemy that's beating you down. The actual math isn't as important as the feeling the player has when they gain TP in each of these ways.
In FFXI, a skillchain was formed when two players used weaponskills one after another, on the same enemy. If they both hit, and if the two weaponskills formed a compatible chain, a skillchain would be created. The enemy would be dealt bonus damage with an elemental type related to the weaponskills used. There was a large chart containing all the weaponskills in the game and how to make all the compatible chains with them (on the internet, players had to figure it all out). You could even chain the chains, so up to four players could cooperate to make a big chain with multiple bonus effects.
Now here's why I think battle regimens are worse than skillchains: You can't do them by accident. You see, when playing, you will naturally use your weaponskills whenever you can. They are extra-cool attacks that deal more damage than basic attacks. If two players happen to use them consecutively and they were compatible, a skillchain would result. I'm sure some early players were surprised by this (not everyone listens when you tell them how to play your game). They didn't need to know how to do it before they did it. In contrast, battle regimens do not work unless multiple players deliberately set out to do them. Worse, they are not something you do when fighting alone, not at all in the normal course of battling a monster. You simply cannot accidentally do one. This is bad. If you have a cool combat system that other MMOs lack, you want your players to find it. You need players to be able to do it rather easily. You want the good players to be able to work with the not-so-good players and still have your cool system work out.
Think about this situation: alpha-type player A knows everything about the game. They read the fansites and try everything and are a master of skillchains or battle regimens. Player B is the jump-right-in type who only learns by exploring for themselves, and doesn't really like to take direction from others. They are in a party together. Player A really wants to chain attacks for the bonus. With skillchains, even if A can't convince B to plan for them, A can save their TP until B performs a weaponskill, and then do their weaponskill afterwards. If A knows the skillchain chart well enough, they can also know which of their weaponskills is best to follow whatever B does. A gets all their fun out of it, and feels smart that they were able to chain even with the uncooperative nincompoop B. B is happy too, because they are just going about their business. Perhaps B even learns of skillchains this way, and becomes interested because they can figure it out by watching what A is doing - by playing the game without reading websites or manuals. In the battle regimen world, A cannot get B to press the extra buttons necessary to set up the battle regimen. A is sad and annoyed. B is also annoyed that A won't shut up about it. Further, B is frustrated that they can't intuit how battle regimens work because they never happen as a result of natural play.
FFXIV makes some other improvements to weaponskills, which I like; I just wish they had kept the skillchain system from XI. I don't think they realized how amazing it is and were too focused on making something different. Maybe they even think battle regimens are easier, because there is no timing issue. (With skillchains, if someone was too late in using their weaponskill the chain wouldn't be made.) Sadly, battle regimens instead take the skill out of it (timing it right is a playskill, as is knowing what will chain and what won't). They replace that skill with bureaucracy - an increased amount of menu use is required to activate the system. I wish they had thought more about why they were changing it, and what they might lose when they did.