Way back to when the group was traveling from town to here:

     Anachain chatted up the two elves from town and tried to get more from them than had already been shared.  "I overheard you two talking about the tracks you spotted," she claims as way of starting the conversation.  She rehashes what had been learned - long toed, four clawed tracks that revealed a gait more appropriate to a biped than a four legged creature and fresh moss growing near the tracks, almost as if the forest was trying to hide them up.  Anachain tries to see if they have anything more on the tracks and makes sure the other party members are aware of this information.

     She also coaxes them about something else she says she heard from them - information about a drifter.  "You talked about a drifter you heard about, orders milk and pays in copper pieces covered in mud?  Did you ever get a description of this drifter, other than a big fella?" she asks.  

     Given this information, and as part of sharing it with the others, she inquired with them if any of this made any sense to them.  "Know any creatures or people who can use moss or bits of nature to cover their tracks?  Only using copper pieces relevant to anything?"

(I think some of this may have been shared before but if not it should have been so I am retroactively putting it out there!)  :D

Currently:

     "Are we investigating or trying to sneak up on?" Anachain asks the others in a bit of a hushed tone.  "If it is going to town and making purchases on the regular it doesn't sound like this needs to turn violent?  Perhaps we could just call out and ask it to talk with us?"

Togar flies right over the tree line, near the bridge.  As he shifts and moves position in the air, he senses something.  Three somethings.  He senses excitement, not a good kind of opening-your-birthday-present kind of excitement.  More of a ... lethal ... kind of excitement, the thrill of the hunt.  The owlin's eyes go especially wide, he sees Deniz near the river bank, he quickly casts mage hand that appears in the ethereal form of a bird claw, it shoots forward toward Deniz and down near the ground / waterline.  He makes the hand point urgently toward the area under the bridge, then it extends the thumb, index and middle finger while holding back the fourth and fifth claw, indicating "3" and then pointing back under the bridge.  If Deniz looks up, Togar continues flapping and points under the bridge, waving his wings and circling.

Deniz is just in the process of casting a magic spell over the water when the ethereal hand appears. He cuts his cantrip short, observes the message, and glances up at Togar and the bridge, then quietly stands and approaches the others on the bank.

To his companions he quietly says:
Prepare yourselves. We may be in an ambush. Three, under the bridge. Don't look now!

Then turning to Ashton he adds in Elvish:
Call to your companion. He may be in grave danger.

Perception: 18 if Deniz can see anything from his brief glance at the bridge

Deniz takes a look under the bridge, the lateness of the evening and the bedraggled vines which hang over the bridges edge, swaying underneath do not help him see clearly, but aside from the bikes he sees no movement, no bubbles in the gently running water, no silhouette in the mud. 

Ashton shouts up to warn Darryl, who begins moving away from the bridge. Togar feels the thought patterns speed up, activate, not wanting to lose their chance. Deniz watches as the vines begin retracting upwards, up to the bridge forming quickly, wrapping around themselves and twisting into the crude form of a humanoid, three of these corrupted plant creatures rush Darryl and attack. 

((Will wait for initiative to be rolled and all but will note that once Anachain and/or Myrth saw the signal about under the bridge, the invisible Myrth would have flown there using full movement and dash to take a look around with their darkvision / Devil's Sight.  Anachain also has Devil's Sight with a 120' range so she sees normally in darkness....))

(((And question!  The bridge is over... a stream?  River? Creek?  And any indication how deep and or swift the water is?)))

Kulloda watches the vines come to life and reach up and over the topside of the bridge to attack the elf up there.

"Hmpf, elf should come down. Get attacked now because scared," Kulloda says

Togar climbs 30 feet in the air, to a height of 40 feet over the vine creatures, as he does so he creates a 10 lb block of metal in his claws, then trying to line up the one in front of Darryl, he drops the block onto the vine, trying to crush it.  

Dropping conjured 10 lb block : 8 to hit, for 12 points of bludgeoning damage.  

     Myrth is indeed flying full out towards the underside of the bridge.  The invisible imp sees the creatures form atop the bridge but there could still be more or such under the bridge to be investigated... And as the Imp isn't totally suited for combat anyway, their invisible investigations of the underside seems the best first bet for them.  (40 ft flight speed, another 40 w/dash being used if needed.  Invisibility still engaged.)

     Anachain, for her part, is in a Blast First, Question Later kind of mood so she sees this unknown creature atop the bridge near the guide and lets loose with an Eldritch Blast.

EB vs Green Guy near guide:  9 to his for 9 force damage...  (It likely goes wide... Cause it was a warning shot.  Yeah, a warning shot!  That's it.  That's the ticket!)

“Dumb plants,” Kulloda grumbles, working himself up into an angry rage because of how dumb looking the vine creatures are.

Kulloda runs up the bank to get to the eastern end of the bridge. As he does, he grabs a javelin from his back, and as soon as he gets up the bank and close enough to be in range, he hurls it as hard as he can at the closest vine monster.

Bonus Action - Rage

Movement - 30’ up the bank to the road/start of the bridge

Action - Javelin - 14 to hi for 12piercing (or including 2 from Rage)

The elf closes his eyes, rubs his conch shell, and hums a magical tune. As his eyes snap open, a soft pale beam of light illuminates the bridge, engulfing one of the vine-creatures in ghostly flame...

Moonbeam on the front blight: DC 13 CON save. 7 radiant damage on fail, 3 on pass.

From his hiding spot, Grimrin steps out with an arrow knocked. He takes aim at the nearest creature and fires his shot before sidestepping behind the next tree to disappear from view again.

Action: 14 to hit, 7 piercing damage

Bonus action: Hide (24)