Ready Marilith

[No brains]

I think I've found a peculiar interaction between the ready action and creatures with the reactive trait: they could meet their ready condition multiple times a round.

A creature with reactive can take one reaction per turn. In the case of the marilith and hydra, the intent was likely to give multiple opportunity attacks, allowing these creature to lock down an entire party by proximity. The marilith also gets to use its parry once a turn.

What interested me in the interaction with the ready action is that the only limitation specified to the number of times a readied action can occur is, "Remember that you can only take one reaction a round." In theory, when this restriction is bypassed, flexible wording of the trigger condition can allow Reactive creatures to trigger every turn.

If a marilith wants to taunt enemies, it can ready its teleport action to move away when a creature approaches it and do that on every turn, 'peasant railgun'-ing itself a potential 480 feet a turn vs a 4-member party.

I think my preferred method of abusing this would be to give a marilith an automatic rifle (or 3) out of the DMG and have it lay out a suppressing fire when enemies break cover. The burst fire option allows it to hit multiple creatures a reaction unless the enemy can coordinate around a cheating machine gun demon! How ridiculous is that!

P.S. Given this is all in core, I'm sorry if this is old news. I'm just having fun with my new idea for a high-level encounter.:smallsmile:

[MaxWilson]

Core yes, but this is the first time it's been brought to my attention. Marilith multi-teleport is an interesting application.

Personally I would not allow the same readied action to be triggered more than once, because it's inappropriate from a diegetic (narrative) perspective, but it's an interesting RAW technicality that could lead to other interesting RAW technicalities such as releasing a dozen Fireballs from a single 3rd level spell slot, if you've shapeshifted into Marilith form. That is, if you give up on things making diegetic sense and are playing a strictly Rules As Written game, this could be an entertaining combo.

Thanks for sharing!

[No brains]

The diegetic concern is what made me think of a machine gun marilith. Suppressing fire is one of the ways this ability could be used in a way that makes sense. The demon just turns on the bullet hose and if something breaks cover it gets shot. A marilith tele-dancing one step a turn could conceivably work with how a reactive creature experiences time, but it would also make it look like Daffy Duck. Sub-optimal both dramatically and tactically.

As for the fireball, that's an interesting case since readied spells have their own rules. Would the fireball-marilith need to keep concentration on all the instances of fireball? Would spell concentration end after the first spell ends (instantaneously)? I'm pretty sure that even on a held action, only one successful fireball can come out of a spell slot. Finally, if the enemy can hold their horses for six seconds, the spell slot is lost no matter how many fireballs could come out (I may be mistaken).* Even so, using a wand or other magic item can add a layer of sustainable complexity to this. I should look into this more.

*I may be mistaken, but I think this is how readied spells work. I thought I had read that before, but I can't find my source and re-reading the rules doesn't quite back that up. To ready a spell, one casts a spell as normal, which typically involves expending the spell slot. Then concentration is held on the spell until a suitable trigger occurs. It's left vague as to whether or not a spell can be continuously held over several rounds or even if the player can decide on another triggering condition.

[Yora]

I would say you can ready an action only on your turn, and once that action has been performed, it's no longer readied and can not be triggered again.

The marilith can still do other reactions that don't need to be readied, like opportunity attacks and its parry ability.

[sandmote]

As for the fireball, that's an interesting case since readied spells have their own rules. Would the fireball-marilith need to keep concentration on all the instances of fireball? Would spell concentration end after the first spell ends (instantaneously)? I'm pretty sure that even on a held action, only one successful fireball can come out of a spell slot. Finally, if the enemy can hold their horses for six seconds, the spell slot is lost no matter how many fireballs could come out (I may be mistaken).* Even so, using a wand or other magic item can add a layer of sustainable complexity to this. I should look into this more.

*I may be mistaken, but I think this is how readied spells work. I thought I had read that before, but I can't find my source and re-reading the rules doesn't quite back that up. To ready a spell, one casts a spell as normal, which typically involves expending the spell slot. Then concentration is held on the spell until a suitable trigger occurs. It's left vague as to whether or not a spell can be continuously held over several rounds or even if the player can decide on another triggering condition.
You cast the spell once:

When you ready a spell, you cast it as normal but hold its energy, which you release with your reaction when the trigger occurs.
I think this would only allow you to release one fireball, because you only cast the spell once as you readied it.

On the other hand, the rules also say the following (emphasis mine):


You can't cast another spell during the same turn, except for a cantrip with a casting time of 1 action. So I suspect a creature with Reactive could cast counterspell or shield every turn for as long as it has spell slots remaining.

Edit: which I realize doesn't really apply to the issue of readying. But it might apply if you're trying to break things, and is the closest comparison I see rules-wise.

[sithlordnergal]

You cast the spell once:

I think this would only allow you to release one fireball, because you only cast the spell once as you readied it.

On the other hand, the rules also say the following (emphasis mine):

So I suspect a creature with Reactive could cast counterspell or shield every turn for as long as it has spell slots remaining.

Edit: which I realize doesn't really apply to the issue of readying. But it might apply if you're trying to break things, and is the closest comparison I see rules-wise.

I agree with you that the rule restrictions might prevent rapid fire Fireballs, but its not super clear. That said, your second rule about only being able to cast a cantrip only applies to Bonus Action spells. You can cast multiple spells that require actions or reactions per turn without having to cast a cantrip. I.E. an Eldritch Knight can use their turn to cast Scorching Ray, then Action Surge to cast Haste, then use their Haste action to make an attack, and then later use their Reaction to cast Shield, all on the same turn.