It was pretty clear to everyone present that this Chaos Space Marine was using all the selfcontrol he had to not just go nuts and slaughter everyone. his breathing was a hollow-deep ragged intake and outbreath that sounded like a Bloodthirster's heavy breathing.
a Mark was on his Chest, center-mass, Looking like it was branding right onto the Ceramite Armour Plating and through it unto his skin, except that the mark was only visible on the outside right now (since he was wearing his power armour). It was glowing a burning fire-red with an outlining of Brass and Burnished Bronze, the Mark was of course the Mark of Khorne, Gifted only to his most Worthy Chosen Champions.

Scarax was already holding a great level of contempt for this warlord. yeah he looked rather scary with that bleeding armour of his, but so did an Imperial Warlord Titan and Scarax have after all slain one of these colossal warmachines by continious chopping at it's ankle-servos.
The main reason for this scornful hate and pity came from the reason that the Warlord didn't just go claim it on his own. If he was worthy of wielding such a grand weapon of Khorne, then he should go there himself to claim the rights to carry it in blood combat, not by sending others to claim it.
But Scarax remained 'calm and collected' and didn't say anything. Cuz if he was to be 'ordered' there, then he'd do it of his own free will and do it in the Name of the Bloodiest gods of them all and just claim this axe for himself and woe be onto any who'd try to take it from him. Be they comrade in hunting it, or the Lazy Warlord himself. They'd all die and Scarax would claim their skulls in the Name of Khorne and drink their blood to anoint himself in the honor of truely claiming this weapon as his own.

All of this was of course not visible on him. He was standing tall (a bit taller than most Space Marines), his armour lightly hissing and steaming with vapor, making his appearance quite the more frightening to everyone else.