He'd been trying to snag behind the creature's neck, but the reaction had him taking rapid, surprised mental notes. Neck extends. Extremely flexible. Muscled. That--was unexpected.

He tried to turn aside, but the blow still sent him reeling; between trying to avoid it and simply being struck he'd rapidly lost his grip on the creature. He took a swift few paces back, shaking his head briefly and blinking to clear his head from the strike. His sense of hearing was ringing, a brief fuzziness taking his vision as the blood flow to his head was briefly interrupted. But it hadn't really harmed him; it was a hit, but little more than a blunt punch. Which was fair, given the fact that this was a spar.

Vargas quickly assessed, and then--careful not to strike with his actual arm-spikes--lunged forward and aimed a backhand strike with his long left forelimb, attempting to hit Phlegethon across the head or jaw. His intent was to stun it, if even briefly, in turn--a punch to the head, though backhanded, rather than a neck-punch to the... well, neck.

Round: 2/5
Attempt: Backhand Phlegethon, possibly stun?
Defense: Some Quills?
Injuries: None

@Phlegethon

Phlegethon was beginning to notice two things: one, slamming with its face and neck was a nice way to stun your foe and yourself; and two, it was a sitting duck, even half-submerged in the water. If it ever hoped to go on the offensive, it would have to resort to dragging - ah, no.

The creature reeled its head back, far too late to avoid a hearty smack that only exacerbated the faint sensation of buzzing in its brain. All of this hitting was already weighing heavy on its thought processes. A bit blindsided and seeing double, it took to hunting tactics. Reeling back its neck and striking out, Phlegethon aimed somewhere in the direction of Vargas's arm, hoping for one of those blades to catch in its baleen. It'd be a start.
Round: 2/5
Attempt: Latch onto Vargas
Defense: ? Little Spikes? (and being slippery?)
Injuries: Squished bones and a little headachey/concussed

@Vargas

It lunged, and he wasn't sure what it had been trying to do, only that it slapped into the slop and--missed? The Overseer pressed his advantage at once; Phlegethon had overextended (or had it? wasn't it... extensible? he'd never seen anything like that, before, but maybe it couldn't 'over' extend at all) and he leapt for it.

He was heavier--his aim was to grab it, to drop his weight, to get limbs tangled around its neck behind its head the way one might hold a snake. With luck, he'd get a hold on it and let it exhaust itself struggling.

The only issue was, what if it were snake-like--a constrictor? Muscled, able to coil about him-? Ahh, well; quills and spines ought to help well enough with that. Vargas's mind wasn't thinking all this out word-for-word, of course; he was acting rapidly, on instinct and with the experience of centuries of bloody battle.

Round: 3/5
Attempt: Wrestle Phlegethon
Defense: Some Quills?
Injuries: None

@Phlegethon

Phlegethon knew it had made a poor decision the moment its bottom jaw was slicked over with mud. Before it could manage to draw itself up, the Overseer had monkeyed himself onto its torso, limbs tangled in a headlock. Its head twisted around a few times, which was a futile effort. The other just had too strong of a grip on it.

Fortunately for Vargas, it was not much like a constrictor. Its torso tended to follow whatever predetermined path came up with the motions of its head and tail. There wasn't much flexibility there aside from the sort necessary to squeeze through a tight spot that its eye could. Although, it could still try to find leverage with its tail. The Overseer was certainly heavy, especially on land, but Phlegethon couldn't help but push for a bit of water-based combat.

It pushed and extended its head upwards, then arched its back as far as it could. Flukes pressing hard against the murky bottom of the shore, Phlegethon aimed to stretch Vargas out as far as possible. Then, in a quick motion, the slime-beast thrust its bulk sidelong towards the water. It took a deep breath and held it.
Round: 3/5
Attempt: Roll into water?
Defense: ? Little Spikes? (and being slippery?)
Injuries: A little concussed

@Vargas

Vargas was not, in fact, capable of breathing underwater. When he felt the slick, slimy creature beneath him flex its muscles and throw itself in, he had time to take exactly one half a gasp of air before both of them went under. The cold was always a shock--the not-breathing, as much so.

The Overseer struggled to get his feet under him, without losing grip--and to use his size and strength in one wrenching blow, the much beneath as questionable leverage, to thrust them both back onto dry... ish... land.

Should he fail at this, he'd need to relinquish his grasp--and he wasn't ready to do that; not yet.

Round: 4/5
Attempt: Back onto 'land'
Defense: Some Quills?
Injuries: None

@Phlegethon

In just a few motions, this had become quite the wrestling match. While Phlegethon fought to stay beneath the water, Vargas fought to stay on land. Ultimately, the Overseer won out, hauling the both of them towards land again.

The slime-beast twisted in his grip so that its head faced his underside. Then, rather horrifically, it started to make a gargling noise. Seeing as it was the one shoved halfway into the mud, Phlegethon wasn't that concerned about setting itself on fire. Retching, it aimed a glob of gel at Vargas's limbs, wrapped around its neck, still.
Round: 4/?
Attempt: Spit up some slime on Vargas
Defense: Spines and being slippery
Injuries: A little concussed

@Vargas

The thing was spitting pyrogel at him. Now, Vargas wasn't a complete moron, and he WAS rather familiar with the magic of the caves. His thought, therefore--along with a memory of recently being set on fire--was something along the lines of, Uh-oh.

He quickly released Phlegethon entirely, springing back--and then, in a moment of brilliant inspiration, just dashed forward to wipe the goop back off on the oily beast itself.

Undoubtedly, he'd not get ALL of it off, but maybe if Phlegethon was equally tainted by the stuff, he'd be less likely to... well, set it on fire.

Maybe.

Smear.

Round: 5/?
Attempt: Wipe some all over Phleg
Defense: Some Quills?
Injuries: None

@Phlegethon

The moment Phlegethon felt pressure release on its neck, it twisted its whole body to be upright again. Vargas had sprung back, apparently familiar with the tactic of carpet bombing one's hands to get them off. He also came back, only to rub the pyrogel onto its face. That was a bit of a damper on its plans, but oh well.

Time to try the whole wrestling thing again.

In an instant, it coiled up and lunged again, seeing a little clearer now and aiming more properly at Vargas's forearm - somewhat close to the wrist.
Round: 5/?
Attempt: Take Vargas by the arm
Defense: Spines and being slippery
Injuries: A little concussed

@Vargas

He felt the grip slam down on his wrist, felt the weight, the leverage pulling him off-balance. He stumbled, and immediately reared back his other forelimb. This swept forward with all his strength behind it, aiming a simple closed-fisted punch for Phlegethon's snout.

Briefly, he debated whether letting the creation's neck go had been a good idea. But what was the alternative--to be set aflame?

It had made a good decision, he decided--weaving magic with its physical strength. Thus far, it seemed to be a good design, though neither of them were truly pulling ahead--not yet.

Round: 6/?
Attempt: Punch Phlegethon
Defense: Some Quills?
Injuries: None

@Phlegethon

As Phlegethon focused on hauling ass, it didn't exactly account for the other free arm with a seemingly limitless range. Well, longer than its own, seeing as it had very short arms, if any at all.

So, it was a little late to react once the fist smacked into its snout. It metaphorically saw stars with a waa! Shaking its head, disoriented, Phlegethon's eye scanned for an opening. Currently, there were no hands on it, some amount of pyrogel, and a whole lot of mud around it.

Oh, brain wave. And one that might not require that much aiming or coordination

The slime-beast buried its bruised snout into the shallow water, driving it through to get a good amount of mud on top of it. Then, in a quick motion, it flicked it upwards. Hopefully into some eyes. Maybe.

It could also just be flopping into muddy water in a tragic failure.
Round: 6/?
Attempt: Phlegethon used Mud-slap!
Defense: Spines and being slippery
Injuries: A little concussed

@Vargas