Spawn of the Old Ones, Preying on Your Mind

If there's one area of Arkham Horror that I've seen questions about many a time over in r/arkhamhorrorlcg on reddit, it's the interactions between the Spawn and Prey mechanics when someone draws a card from the encounter deck.

Both of these keywords are explained in the rules reference document, but even when you sit down and read through the reference, it isn't clear on how an Acolyte behaves compared to Conspicuous Staff or to Beings of Ib.

What I've done below is generate a flowchart for players which takes into account Spawn, Prey and Aloof, and will help you determine just where that latest enemy should appear once your Seeker has drawn it...

Before we make with the flowchart, here's a quick high-level reminder of what the three rules in question do - for full details, I refer you back to the rules reference.

• Aloof - An enemy with Aloof spawns without engaging to an Investigator, and you have to engage it in order to attack it. (Page 4)
• Prey - Indicates that an enemy has a preference when it comes to which Investigator it will target when given a choice. (Page 17)
• Spawn - Dictates where an enemy may enter play when drawn from the encounter deck. (Page 19)

You can see why these might get muddled up, even just from the paraphrasing above - all three rules can interact with who an enemy will engage, if at all, and can combine to lead to some unexpected board states.

Going with the flow(chart)...

OK, now let's work through this, one step at a time.

Q1 - Does the enemy have a Spawn instruction?

• If no, proceed to Q2.
• If yes, proceed to Q3.

Q2 - Does the enemy have the Aloof keyword?

• If no, spawn it at the same location as the investigator who drew the enemy, engaged with them.
• If yes, spawn it at the same location as the investigator who drew the enemy, but not engaged with any investigator at that location.

Q3 - Is there a location in play which satisfies the Spawn instruction?

• If no - for example, a specific named location is not in play, or if there are no empty locations when an Acolyte tries to spawn at one - then the enemy does not enter play and is discarded.
• If yes, proceed to Q4 - if there are multiple locations in play which will satisfy the Spawn instruction, the investigator who drew the enemy determines which location before moving to the next step.

Q4 - Are there investigators at the location the enemy will spawn at?

• If no, the enemy spawns at that location, but does not end up engaged with anyone.
• If yes, proceed to Q5.

Q5 - Does the enemy have the Aloof keyword?

• If no, proceed to Q6.
• If yes, the enemy spawns at the Spawn location, but does not engage anyone at the location.

Q6 - Does the enemy have a Prey instruction?

• If no, the investigators choose which of them at the Spawn location are engaged by the enemy.
• If yes, proceed to Q7.

Q7 - Is the Prey instruction in the form "Prey - XXX only", such as on Guardian of the Crystallizer?

• If no, the enemy engages the investigator at the location who best fulfills the Prey instruction (for example, the lowest Intellect at that location, even if not the lowest Intellect in play).
• If yes, proceed to Q8.

Q8 - Does an investigator at the Spawn location satisfy the "Prey - XXX only" instruction?

• If no, the enemy spawns at the location without engaging an investigator.
• If yes, the enemy spawns at the location, engaging the Prey that satisfies its requirements.

The last three steps are in the flowchart because the second bullet point of the Spawn section in the rules reference tells us what happens if there isn't a Spawn instruction - i.e., what we see when we drawn an enemy that engages at Q2 of this flowchart. Because we're told what happens in that case, we can infer that it doesn't happen if there is a Spawn instruction, allowing the enemy to "decide" who to engage - and when it can decide, that's when Prey kicks in.

And, yes, going by the third bullet point of Prey in the rules reference, it would be possible for an enemy to trigger Spawn, then Prey, and end up not engaged with an investigator even though there are investigators at its location. I haven't cross-referenced the list of cards with the two keywords to see if such a case is currently possible, but better to work it through than not. There's nothing stopping an investigator at that location choosing to engage the enemy on their turn and try to defeat it, of course, they're just not automatically engaged by it as it enters play.

Anyway, I hope this process makes it simpler for you to figure out where your next enemy should enter play, and who is going to need to deal with it.