How complex can my commands be with the Conjure Animals spell?

Question

How complex can my commands be with the conjure animals spell?

Can I command a conjured animal to do multiple things, and at any time? Can I change my command any time or on my next turn?

Answer 1

The spell Conjure animals gives you a pretty good idea of what you can do concerning animals that are conjured by the spell.

You summon creatures, and can issue verbal commands to them. They attempt to follow the commands as well as they can, and any new command you give them supersedes any prior commands.

If you summon more beasts of a lower CR (rats for example), you can issue them each individual commands and they will obey to the best of their ability. As is normal, Any new commands given will supersede old commands.

Issuing a command doesn't require any actions(as specified by the spell), but animals will likely not remember commands you give them beyond the first.(Animals aren't normally intelligent enough to do so)

However, the things that you could do with this spell should be ran by your GM, as he may have a different opinion.

Answer 2

You also asked:

Can I command a conjured animal to do multiple things, and at any time? Can I change my command any time or on my next turn?

The spell description says:

Roll Initiative for the summoned Creatures as a group, which has its own turns. They obey any verbal commands that you issue to them (no Action required by you). If you don't issue any commands to them, they defend themselves from Hostile Creatures, but otherwise take no actions.

Would it help?

The creatures have their own initiative, and you have yours. Unfortunately, initiative is sort of backwards when it comes to awareness. If you roll the best, you go first and don't know what others will do on their turns. If you roll the worst, you can respond to anything. Reactions allow a counter-response to many things at any time, and a non-action for a verbal command could likewise be at any time.

But if you talk once before their initiative and once again afterwards, it's really just a sequence of 2 commands. And if you talk once before your turn and once afterwards, but both are before or after theirs, it's really just 2 contradictory commands. So the amount you can speak is the real limitation. For that...

the Suggestion spell is a good guide.

Here it is with the saving throws and conditions of the Suggestion enchantment edited out, such that it might read:

You command a course of activity (limited to a sentence or two) and magically influence a conjured creature (or several) you can see within range that can hear and understand you. The suggestion must be worded in such a manner as to make the course of Action seem possible.

[...] It pursues the course of Action you described to the best of its ability. The suggested course of Action can continue for the entire Duration. If the suggested activity can be completed in a shorter time, a creature will then act as if you haven't issued any commands to them.

You can also specify Conditions that will trigger a Special activity during the Duration. For example, you might command that a creature attacks the nearest cultist, or preferably attacks any who attack you. If the condition isn't met before the next command or the spell expires, the activity isn't performed.

Answer 3

It's a circus.

In combat, each round is about 6 seconds, and includes a flurry of activity. Phb, combat, page 186.

There's something called "zero-initiative time for soliloquy" that's been around since 1974. It's practically a part of TTRPG DNA. It means each round you get time to speak or shout up to 10 words, over the top of everything else that's happening. More than that is a monologue and takes your action.

Stuff like, "You shall not pass!" Or "Find the halflings!"

Unless your caster has telepathy, that limitation is part of the 3-ring circus that is Conjure Animals or Conjure Woodland Creatures. And in the first round, you've just spent your action on a spell with verbal components, so most of your speech time is already used up.

What's more, these are just Beast stat blocks with fey spirits shoved into them literally seconds ago. They don't have names, they're maybe barely aware what species they are. They have your voice in mind to obey because you summoned them. But if they can't understand you or hear you over the din of battle, they'll just defend themselves. And it's not your decision as caster to decide what that means.

Conjure Woodland Creatures is even worse.

Pixies and Sprites have Invisibility at will, but not See Invisibility. So these idiots are gonna be tripping all over one another, or at best shouting a Sylvan form of Marco-Polo all the time. Blink Dogs have sensitive hearing and teleportation, so if they don't have orders, they'll teleport over to you for further instructions as an effective means of "defending" themselves. If the battlefield is too loud, you'll suddenly be surrounded by happy puppies waiting for instructions. Hags have an indiscriminate fear effect on all humanoids. And Satyrs are just... naughty.

The caster can use Thaumaturgy to amplify their voice 3x, but that will put a target on their back. Add a top hat, big shoes and a pony, and you've got a full 3-ring circus.