Marbas advanced as the order was given. Uriel declared that Rayvius was on point. A good decision if ever he had seen one. He watched as Hakael followed the leader closely. The last in line was always Marbas. The marine refused to let anyone fall behind, his sense of brotherhood was strong. That, and he really liked having nice long firing lanes; being used to heavier weapons did that to him, and old habits died hard. He scaled a little pile of rubble that gave him an even better view and rapidly, even violently, emptied half a drum on semi-auto. But every shot was a lethal one, despite the fury in his marksmanship. He had his bolter firmly by the pistol grip, and the left leg of the bipod as he fired, giving him a nice stable grip on the thing for firing on the move. It was also ideal for longer shots given the lack of stable platforms about. With only his iron grip, he made do. Unfortunately, in making do, he had lagged behind just a little, and he dashed to catch up. Thankfully, however, he hadn't caught all the way up when he realized that there was a Tau mech rushing the rest of his brothers. The thing had crested a blind ridge. Rayvius called it out in a timely manner, of course, and the astartes acted immediately, mag-locking his bolter to his thigh and grabbing a pair of blind grenades, which he lobbed as hard as he could toward the thing. The first one burst nicely right in front of the machine, providing a thick screen, and temporarily blocking its sensors as the thing tried to light up one of his squadmates. The second grenade went off in mid-air, bursting just as perfectly right in front of the mech, screening its advance. The thing was blind now, and the clouds were small enough that its location was easy enough to discern, even though it was completely obscured by the cloying mixture of smoke and chaff that hung steadfast in the air.

Everyone was scrambling for cover and doing their best to ruin the pilot's day, and Marbas was no exception. However he wasn't in need of cover just yet. The Tau walker hadn't gotten a bead on him before the grenades had gone off. That hadn't stopped it from trying to light up both Hakael and Rayvuis, though. Both warriors had wisely taken cover before getting blown to pieces. And now its targeting systems were having an awful time, so it was time to strike, time to show the pilot who was in control here. There were still plenty of regular firewarriors about, though. Their counter strike had to be swift and merciless. Marbas would start them off with the first thing that came to mind. With the battlesuit waving its guns about, cutting through the cloud that had stopped it dead for an instant, he had to do something. That something was toss a plasma grenade toward its feet. Then he made the critical realization that the big guns had lured him to where the smaller guns could light him up quite happily. Not so worried about the small-arms fire that was chewing up his breastplate, the marine took a knee and returned fire before the enemies more serious rounds found their way to his helmet. He stayed still for just long enough to clear a nearby shell-scrape so he could avoid getting any kind of backlash from either the grenade he had thrown, or the battlesuit that had to deal with it. Neither sounded particularly pleasing, though he'd tangle with plasma long before he would let the xenos get away with anything.

The Tau who had to give up the trench were obviously not pleased. It was understandable, though. The four of them each got a bolt round to the head. The proximity of the xenos to the astartes, however, meant that the rounds didn't even have time to explode before they were through the squishy alien skulls and into the ground. The kicker charges rammed the bolts right into the brains of the firewarriors, and the rockets ripped them the rest of the way through. Burnt blue blood and fried xeno brains now thoroughly coated Marbas and he chuckled. So much for camouflage patterns. He was almost certain that the machine spirit was chuckling with him. It liked to see the xenos and the heretic die as much as any astartes. To add insult to mortal injury, the fresh corpses were crushed under his weight as he combat-rolled into the trench, poking his head out the other side to provide more fire support to the squad's flank. The last thing they needed was a surprise attack while a battlesuit rampaged around in between them.

Indeed, a small group almost pulled it off. Not that they could do anything. A small group of Tau, leading about the same number of drones was trench-hopping to get into position. Marbas chuckled, smiling as he picked off a few of the drone operators. Then, firing his bolter one-handed, he fiddled with a blind grenade with his free hand, tossing the thing toward the group. He netted four more kills before the explosive went off, scattering haywire chaff and infrared blockers everywhere within the cloud of smoke. Only two drones were left, if the explosions inside the cloud were anything to go on. Machines really didn't like that stuff. But they disliked the Emperor's fury even more. The last of the warrior's drum ripped through the air where the enemy had been. There was nothing left of that attempted ambush, and the marine turned back to his brothers, hoping all was going well with the battle.

"How's it looking, brothers? Are there going to be more of those things?" Marbas would be happy to redistribute some ammunition on the fly if they were going to be facing more of those things, or even other nasty targets. If it had occured to him, the space marine supposed he could have just tried out a drum of kraken rounds on the battlesuit. He supposed he still could if it was going to be a problem. No sense wasting them on regulars, though. The Tau's armour wasn't designed to stop much more than a slap, it would seem...