Since the rogue takes 2 turns during the first round of combat that means he gets 2 reactions that round, right?
Yes. Sorta.
He get's 1 reaction per turn, and get's an extra turn. But if 2 people run by you between your first and second turn, you can only use 1 oppertunity attack.
So it really depends on inititive order.
So let's say the rogue starts an encounter without being surprised. He/she can take a reaction between the time the initiative order starts and the first turn at the full initiative mark. Then in between the first and second turn (initiative -10 as per the feature) he/she can take another reaction. Finally in between the end of the second turn and the start of the 3rd turn during round 2 he/she can take a 3rd reaction. Reactions become available again at the start of each of your turns but can't be used during your own turn. So this would give the rogue 3 reactions to play with in total so long as the rogue is not surprised every encounter between round 1 and the start of round 2 for the rogue.
EDIT: For clarity here's the copy pasted section of the rules I'm refering to:
"When you take a reaction, you can't take another one until the start of your next turn." Page 70 of the Basic Rules PDF under Reactions.
Noctaem wrote:
Interesting change to the rule. I hadn't noticed, good to know. So you can ready an action on your turn and trigger it yourself, like saying I ready to attack as soon as I move next to an enemy and then move next to one triggering it in the process. This is interesting if there's features, items, spells, etc that give bonuses to readied actions. Though that does mean that you lose your readied action AND your main action during your turn until the start of your next turn which in most cases is not a good idea to begin with.
First time poster here, thanks for having me 
I have been following some of the rogue rules threads and wanted to highlight something I noticed in the Basic Rules.
Page 72 under Ready
"Remember that you can take only one reaction per round."
As mentioned by another poster, pg 70 under Reactions it clearly states, "When you take a reaction, you can’t take another one until the start of your next turn."
So, taking both of these rules into consideration, RAW would imply that if you take a reaction in round 2, regardless of how many turns you have, you may not take another reaction until the start of your first turn in round 3. Therefore you may use a reaction on any of your turns, but only 1 reaction per combat round.
Thoughts?
Apologies if this has already been raised/ clarified in another thread.
The problem is that the first rule which states you can only take one reaction per round doesn't take into account the fact that the rogue can gain multiple turns via this feature or that any other game element might have multiple turns in a round. The second rule which states that you can't take another before the start of your next turn does. My guess is that they fumbled there. The answer isn't clear because the rules contradict each other in the case of a rogue with thief's Reflexes. I've sent a tweet and we'll see what happens.
MythsandLegends wrote:
I suspect the line on page 72 is just an incorrect reminder that the line on page 70 said something which it did not say.
It does not appear that page 72 is listing any specific rule about reactions when used with the ready action. If it had, then it would have overridden the general reaction rules.
I would say that the Thief's Reflexes class feature is breaking the general rule of "one turn per round" and thus also "one reaction per round." In this case, I would be content to say that the specific class feature breaks the general rule, and therefore it's okay to take two reactions in one "round."
As far as using the word "round" itself on page 72, that is a little ambiguous and goes back to the debate about initiative round vs. cyclical "round." I agree that it's probably a remnant of something, because a cyclical round is only implied in the Basic Rules in the form of "until the start of your next turn"- or "on your turn"-type wordings, even though it is far more important than the literal initiative-based round.
Noctaem wrote:
Noctaem wrote:
I haven't gotten a response yet, perhaps if others were to ask as well it would increase the chance to get a response :p
I sent my question as:
"Page 72 of the basic rules states you can only take one reaction per round. Page 70 states one until start of turn help?"
lawrencehoy wrote:
Noctaem wrote:
So Mike Mearls finally answers my questions. I still think there is quite a bit of confusion in the rules, but it's better than nothings.
@mikemearls Is the RAI for characters to have only 1 reaction per round?It's under 'Ready' but not in the Reaction section of the rule.
Noctaem wrote: