abirdcall
(she/her)
I rule it:
The PC initiating the incident goes first, then everyone rolls initiative for the surprise round. The initiator does not get another action until the surprise round is finished.
There are no surprise rounds in 5e.
Surprise only occurs when a character has no awareness of the threat.
For example: If enemy creatures are sneaking up on the PCs then check their stealth against each of the PC's passive perception. Each PC who has lower PP than the monster's stealth is surprised. Those who meet or exceed are not.
If 2 parties are talking to each other then they are aware of each other.
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I had no idea how many people houseruled the initiative system to allow auto-successes. To me it completely defeats the purpose as a method of adjudicating the transition from time keeping in minutes to seconds.