Quote from RavenTheRogueWizard >>

You'd certainly all know that something was suddenly very wrong - "engulfed by a cloud of thick green smoke, with a sickly sweet aroma reminding you of rotten fruit.
Breathing in hurts, it feels like you're throat is on fire. This smoke is foul, it makes you cough and retch.".

Everyone is very aware of it, it's thick green smoke, and it hurts to breathe. With your strong sense of smell, you'd likely find it even more offensive in odour than others might.
(And I've just noticed that when I described the scene earlier, it said 'tooltip not found', rather than 'blind' - you wouldn't be able to even see well enough right now to clean the plants!)

Inhaling a little deeper, combining your keen sense of smell and your Druid background, you are reminded of a plant called Erwurg. You're sure it's not that, but it seems similar.

OOC- I'm not sure if I'd consider that to be a full turn or not; perhaps the smell and thinking about what it might be is a bonus action, so you'd still have an action. Is that fair?

In this case, suddenly engulfed by a thick smoke Rizo tries to figure out what is happening while coughing and waving his hands trying to disperse the smoke a little. "What's happening?", he calls out. "Are we under attack? Anyone is being attacked?" Not being able to see, he tries to rely on his smell to figure out what is the cause of it. He listens up for evidence of fighting or how the others react. 

(Given that he knows plants that smell like this he tries to recall more detailed information with a nature or survival skill check as action and what would need to be done. Nature skill check would be a normal check +2 and survival would be +6 with advantage, I'll do both and you choose which one you think applies.)

Nature: 12

Survival: 16

Quote from cyreon >>

Quote from RavenTheRogueWizard >>

OOC- I'm not sure if I'd consider that to be a full turn or not; perhaps the smell and thinking about what it might be is a bonus action, so you'd still have an action. Is that fair?

(Given that he knows plants that smell like this he tries to recall more detailed information with a nature or survival skill check as action and what would need to be done. Nature skill check would be a normal check +2 and survival would be +6 with advantage, I'll do both and you choose which one you think applies.)

Nature: 5

Survival: 13

 

(Ah, sorry, so this would be a bonus action? Well, if Rizo can learn that it is probably plant based in a bonus action, perhaps as an action he would cast Detect Poison and Disease and notices the location of poison in a 30 feet radius. Perhaps there is a spot with a higher concentration? Or he might know what could be done to neutralise the poison or disable its source?)

OK, casting 'Detect Poison and Disease' - the whole cloud is within 30ft of you, so you would now be aware of where that ends. You'd also be aware of another source of poison between 25 and 30 ft from you, in a south-west direction. This one though, is not a cloud, but is the same type of poison. 
Now you know the boundary of the poisonous smoke, it would be reasonable to know the source is at the centre of it.

Up next is Lan. Choking, he moans 'Oh no, not this stuff again!', and you hear him stand up and move. Because none of you can see right now, you don't know where he is (so I've hidden him from the map for now).

Next in initiative is Minty.

(unless Rizo wants to use his movement of course)

Quote from RavenTheRogueWizard >>

(unless Rizo wants to use his movement of course)

 Now, he goes to the poison south-west and will check it out next turn.

(Minty, you’re up)

Rizo - I've updated your position on the map, and will send you a DM

Hearing the sound coming from the southwest, Minty moves due south to seek the safety of the trees to better assess the situation.

Minty - map is updated, and I'll send you a DM as well. You still have an action remaining, and some movement. 

The idea of trying to do some of this in a hidden way using DMs is more difficult than I expected - I may give up on that idea very soon! 

Quote from RavenTheRogueWizard >>

Minty - map is updated, and I'll send you a DM as well. You still have an action remaining, and some movement. 

The idea of trying to do some of this in a hidden way using DMs is more difficult than I expected - I may give up on that idea very soon! 

I like it tbh. The exclusivity gives it an air of mystery. But as an alternative you could use spoilers and hope for the sincerity of the players. 

That’s good to hear, thanks! Will stick with it for now.

Minty, I suspect you’ll want to tell me your action in a DM.

Out of curiosity, did Egan hear Lan say, “Not this stuff again?”  Should Egan assume Lan encountered this poison before and might know something?

Yes, you’d all have heard him say that. It’s certainly reasonable to assume he’s encountered it before.

Egan shouts at Alan, “Kid, you know what this stuff is?”

Corvina squawks, “Kid!” She flaps her wings and flutters up and away from the poison.

Whoops.  Or maybe I’ll wait until it’s Egan’s turn.

You hear Minty off to the south say "What do you think you are doing? Stay where you are."

You all hear someone shout "Damn, the poison didn't kill 'em! They're onto us lads, get 'em!"

Next up in the initiative order is Justin, followed by Egan

Justin will make his way East using his warhammer to not bump in to anything. If he's still in the cloud he'll use his action to dash. 

You're out of the cloud, and I've sent you a DM. You still have an action remaining. 

Justin uses the rest of his movement and his action to move 20ft to the South. Keeping his Warhammer ready of course.

OK, map is updated.
Egan - you're up next.

I think I forgot about Corvina earlier. As a creature in the cloud, she also needed to make a Con save, and I don't think that happened.
Can you roll one for her please?

Sure.4