I think he is missing Power Mimicry, Power Absorption, Adaptation and Power Bestowal. The text below highlighted this points. All of these was as a results of the Orc Lord's skills.
Their feet would not stop. Rather, they ran towards the food. Towards the rampaging ogres, their relentless strength! How many comrades were torn to pieces, how many cut down… However! That matter not to the orcs who saw the fallen as merely more food. They were overjoyed. Perhaps they could satisfy their hunger, if a bit. A single ogre had fallen. Immediately, the orcs crowded the corpse and began dismembering it. Drinking blood and devouring flesh. Oh… but that did not satisfy their hunger. But, the orcs bodies had changed–they absorbed the ogres’ strength. Seeing their friends gulped down by lowly orcs, the ogres let out a scream of agony. Lamenting the weakness of their overwhelming power… Gradually, those filled with power appeared from within the orcs.
Devour our comrades, and make their powers ours! Devour our enemies, and make their powers ours!
And again they eat. Without any fear of death. Someday, their power will grow and surpass that of their king. Their king. The ultimate orc, the Orc Lord!
If they just needed to wait that long, they could certainly manage.
The orcs may grow stronger, but they could now hope for reinforcement.
~ Chapter 32 – Stage Curtain Rises
Right now, a single orc can challenge up to three lizardmen. Moreover, their power seems to be increasing. This is, of course, the result of the Orc Lord’s command.
With reinforcements, the orcs will gradually grow stronger, and the defense teams will be eventually overrun.
~ Chapter 33 – Audience
The brave lizardmen warriors, hardened in many battles, this was an unusual sight. A sinister aura wrapped around the orcs. One warrior who was frightened by this sight, tried to retreat a step and fell backwards. Without missing this chance, the orcs swarmed the warrior. He was dragged into the mud and ripped limb from limb. Since the war had begun, he was the first casualty. And that began it all. The orcs that were devouring stranded soldiers gradually obtained their abilities. That ability was not like [Predator], and could not perfectly replicate the skills. Nonetheless, they absorbed the lizardmen’s power to some degree, and shared it among those in their domain. That was one of the effects of the unique skill [Starving Ones]. They were as much one swarm as they were an individual. Again, quiet similar to the shared evolution of the fang wolf species. That is why the previous head was so afraid of letting any lizardmen die. For the sake of not allowing the orcs to develop any further. Although they could not obtain all the abilities of those that ate, they could still acquire some of their special features. For example, the ability of the lizardmen to move freely through mud and swamp. For example, growing scales around their vital areas to defend. This kind of trivial changes they could do. However, that is how they can quickly change the tide of battle.
Gabil released an attack filled with all his might. Combining spear technique and magical energy, a certain kill technique. It was filled with all the strength Gabil had. However,
「Kanrangue!!!」(Chaos Eater) (TL Note: do you want me to translate skill names? Some of these may get strange…
Pointing his spear at Gabil, the Orc Lord devoured the vortex itself. But that’s not all; the spear also began emitting an aura. An ominous yellow aura that attacked Gabil’s very flesh. “It seeks to eat me!” Stumbling, falling Gabil realized. However, the aura would not let him escape…