Can an enemy "surprise" a character with the Alert feat by readying the Attack action before initiative is rolled?

Question

My character with the Alert feat was attacked and received damage pre-combat. Specifically, our party was walking through a dark cave, and on the ceiling there was a swarm of insects (that none of the PCs noticed). Suddenly, the DM narrated that a swarm of insects lunged at my character and immediately attacked him, dealing [x] damage.

I asked him why he didn't ask us to roll initiative the moment the swarm tried to attack me to see who goes first. He said that was because the swarm noticed us and readied its action to attack me when I came into range.

Can a character with the Alert feat be surprised in such a way? Can an enemy who wants to get the drop on a party bypass rolling for initiative versus a character with the Alert feat by readying the Attack action?

Answer 1

Rule 0

On one hand, the DM can do whatever they want; they are the DM. But, by the actual rules in the book...

No, this is not how the rules work as written

The description of Initiative states:

At the beginning of every combat, you roll initiative by making a Dexterity check.

When the creatures are "readying an attack", this is already part of the combat; therefore, Initiative should have been rolled, and you would not be surprised by the attack. This interpretation is backed up in this similar Q&A.

Note that the creatures are still hidden (if you didn't perceive them), so, even though you are not surprised by the combat, not necessarily you know where the creatures are. Even if they are hidden, the Alert feat also states (PHB, p. 165):

Other creatures don’t gain advantage on attack rolls against you as a result of being unseen by you.

By the way, in your text, you mention that the swarm of insects

immediately attacked him, dealing [x] damage.

From this, it is unclear whether the DM rolled an attack roll as well. Even if surprised and attacked by a hidden creature, the creature still has to hit with the attack roll before dealing damage.

Talk to your DM

It seems this situation has upset you. You have taken a feat, giving up an ASI, with the sole objective of such situations not happening, and then the DM pulls up something not entirely backed by the rules that makes the entire point of taking such a feat get thrown away.

Talk to your DM. Tell them that how they handled this situation was upsetting. Explain that the point of taking such a feat is to avoid these situations, and that by house ruling otherwise, they are harming your character's concept. At worst, ask them to let you change the feat, if they are going to keep doing such things, because your expectations when building the character were different.

Answer 2

There are a couple of moving pieces at play in this question, I'll try address each of them. But I'd like to start by pointing out that HellSaint's conclusion is the most actionable advice you can receive - if something in game upsets you, talk to your DM. Now, let's get to it.

Surprise makes people surprised

The way you described the scenario, it is clear that your DM did not play the surprise mechanic as it should have been played.

The correct steps are given in the rules as:

1. Determine surprise.
2. Establish positions.
3. Roll initiative.
4. Take turns.
5. Begin the next round. Repeat step 4 until the fighting stops.

The reasoning given by the DM for not following these steps, appears to have been that the swarm was ready. Let's look in to that.

You do not have to be in combat to perform an action

Actions only exist inside combat. Outside combat, you just do it, no action is needed. Since no actions are ever needed outside of combat, there aren't any rules for them. It's totally unnecessary.

To be clear the idea that you can perform "actions out of combat" isn't completely true, you can perform the same effect as the action, without every taking the action.

For example if you want to chop down a tree, you don't have to use the attack action. You tell the DM your intentions, and they tell you if you need to roll, and then narrate the results.

You can be ready for something outside of combat

There's nothing special about the effects of the ready action that make it impossible to do outside of combat. "When the toast pops, I'll butter it" - why would anyone need to be in combat to do that?!

A swarm of insects could certainly be ready to do something, and when combat starts they continue to be ready. However, what has this got to do with surprise?

I rule being ready using the ready action

While there are no rules for translating pre-combat activities into combat, using actions is a sane way to do it.

When someone is ready for something, I rule they have essentially taken the ready action since that seems to be closest to the spirit of what they requested. However, once in combat they must follow the combat rules:

1. The swarm is hiding in the dark (stealth check), prepared to attack whoever enters reach.
2. You fail to detect the swarm (passive perception), and unfortunately walk within 5ft of it.
3. Determine surprise: The swam has surprised the party. However, the alert feat stops you from being surprised.
4. Establish positions: You are next to the swarm, the party is somewhere behind.
5. Roll initiative: Let's imagine you roll a 20, the swarm rolls a 1.
6. Take turns. First, it's your turn.
7. Since you the swarm has effectively readied an action and it has its reaction available, it gets to attack. At this stage you have your reaction available too, so you could cast Shield, use Protection fighting style, use Parry, Riposte, etc.
8. Now that the readied action has been dealt with, you take your turn.

Because you were not surprised you should have your reaction ready at this stage. This could potentially influence the fight. If you won initiative, you should be able to act before the swarm gets its turn, allowing you to dispatch it.

Actions that initiate combat should happen during combat

There is always discussion about when combat should start. How would you rule the following situations:

• If you unexpectedly throw a punch at someone during a conversation, does the attack land before or during combat?
• If you shoot an arrow from 600ft away at someone who is looking away from you, does the attack happen before or during combat?

Some DMs would rule that the action takes place before the combat starts (as your DM did). But I think that's the wrong way to rule. It doesn't take into account the alert feat, reactions, initiative, or other mechanisms.

This point is always controversial. While stealth vs perception is listed as a guaranteed method of gaining surprise, who is and isn't surprised is down to DM ruling at the end of the day. Even though you have not made a stealth check, and they have not made a perception check, I would rule the situations above using surprise. The attack would be rolled top of the round.

I have found this ruling to be realistic, and give players the opportunity to exercise their agency.