Randall:

Seeing the situation getting rapidly out of hand, Randall considers trying to magically end the conflict but realizes his spell only works on humanoids.  Sighing, he hopes that focusing on the plants will give them a chance to negotiate with the natives.

Invoking his Spirit Guardians, Randall moves up next to Petcan and draws Lightbringer, preparing to receive any incoming attacks.

Spirit Guardians:  DC 16 Wisdom or Radiant Damage within 15':  10

Initiative:  1

Tempe "We are supposed to make allies!" he says as he produces a flame on the tip of his tongue and flies up in the air 

"Stop this," he forcefully shouts Intimidation 17 at the natives.

@Randall

Don't forget to roll your initiative for your turn during Round 1. It will determine in what order your turn takes place.

9 Initiative

Z casts [spell]Blight[\spell] on the plant. Save: CON 14, at disadvantage. Damage is maximised against plant creatures and magical plants, so 8d8 = 64 damage; or half if it saves. 

He then uses his flying speed (boots) to move into the air and out of reach, on the assumption that plants can't fly to engage him in melee or grapple him.

Bow initiative:15

(if it seems the native is controlling the plants bow will use blood curse of the muddled mind to give it disadvantage on con saves, if it doesn't seem to control them nevermind :P)

Than he attacks either the native if it controls the plants or the plants of the native doesn't control them

Attack: 24 Damage: 20

Attack: 20 Damage: 23

Bonus Attack if muddled mind was necessary for the native: 18 Damage: 25

Native's Initiative: 3 

The natives point at the plants and scream in their strange language, then any who live turn and run along the footpath.

Purplewrath's Initiative: 12 

The plants rush through the ring of fire and try to attack anyone they can reach.

(will roll their attacks when I know if any survive)

Round 1 Summary

17. Tempe flies up into the air casting a cantrip and shouting for the natives to stop this hoping to intimidate them to cease any hostilities.

15. Bow unleashes 2 bolts and slows one of the Purplewraths to barely a crawl as it appears severely wounded.

13. Petcan's ring of fire appears around all 5 of the Purplewraths and they suffer 27 fire damage as they rush through the wall, the one with 2 bolts in it collapses dead in it's tracks.

12. The 4 remaining Purplewraths converge on Petcan and each make 2 attacks.

1st Attack: 20 Damage: 5 

2nd Attack: 21 Damage: 9 

3rd Attack: 25 Damage: 10 

4th Attack: 21 Damage: 8 

5th Attack: 6 Damage: 7 

6th Attack: 18 Damage: 9 

7th Attack: 21 Damage: 5 

8th Attack: 22 Damage: 7 

Petcan also needs to make 4 CON saves vs. DC 12 or be blinded by the purple mist.

9. Z casts blight and one of the Purplewraths dries up into a wrinkled husk, dead. (it's save is irrelevant as even half damage would kill it at this point)

3. The natives scream and point at the plants before running off.

1. Randall moves to stand beside Petcan casting spirit guardians.

1st PW's save: 17 

2nd PW's save: 4 

3rd PW's save: 2 

Randall also needs to make 4 CON saves vs. DC 12 or be blinded by the purple mist.

(Everybody is up. Roll initiative for Round 2 and include it in your post for your round 2 turn.)

(PS: sorry, Randall only has to make 3 saves.)

OOC:  By initiative 1 the situation is nothing like it was at the beginning of the round.  Shall we resolve what happens to Petcan before Randall acts?

Yes, that's fair.

It is such a departure from the normal way.

I might just go back to the normal way. I don't want to use the "I roll initiative for everyone" method anymore.

@dm

the plants have to take 24 fire damage if they fail s Dex save, and then another 27 if they try to run through the wall. 
edit: half of 24 on a successful save. 27 is no save. They just take it. 

This may be wrong but I count the area of effect as the ringed wall up to 20 feet in diameter, 20 feet high, and 1 foot thick.

2 scenarios can arise from this:

1. You cast it so they were in the area of affect, the actual fire, and therefore had to make a save or take 24, half if they make the save, and then they exit on the side that doesn't have heat where everyone else is.

or

2. You cast it to pin them in so they were within 10 feet of the wall. They moved through it on their turn and took the auto-damage, no save, and ended up on the side that doesn't have heat where everyone else is.

Is this wrong?

No it is correct; Nschrock its when they end their turn there or walk through the wall of fire:
"One side of the wall, selected by you when you cast this spell, deals 5d8 fire damage to each creature that ends its turn within 10 feet of that side or inside the wall".

I choose the option that did the most damage because I figured that is what you would of wanted, sorry for not asking first or clarifying.

I figured it’s hot in the wall’s whole area, which I thought included the ten foot area where it’s hot. I probably should’ve just cast fireball then, but lesson learned. 

Petcan raises a shield when the plants attack, deflecting all but 3 attacks 

4 con saves against blind

22 11 9 11 

And 3 concentration checks 20  22 22 

I’m blind and wall of fire is gone 

Randall (Initiative 1, Round 1):

Moving up to the edge of the plant’s mist but not entering it, Randall calls, “Come this way, Petcan, and I will heal you,” as the spirits encircle him.

(Still casting Spirit Guardians, but not entering the blinding mist—instead giving Petcan a frame of reference to withdraw to if he wishes).

Randall:

Initiative:  18

( Randall has Spirit Guardians in effect which will affect the plants if the approach him within 15 feet.  He is planning to heal Petcan if he can, but that may take different forms based on where Petcan and the plants fall in initiative.)

Spirit Guardians Damage for round 2 if needed::  11

Round 2 init; 13

Bow shoots 3 bolts at whatever plant is closest 

Attack: 16 Damage: 17

Attack: 7 Damage: 22

BA Attack: 11 Damage: 18

(ooc: to clarify a little, I will reconsider initiative options after this fight, for now include your initiative in your post for your round 2 turn... I have Randall and Bow's, others can post when the hangovers wears off, lol, Happy New Year everyone!)

Petcan initiative 15 

Petcan will follow the sound of Randall’s voice and cast warding wind on himself, hoping to hedge out any further issues with the plants’ mist