Orcs are the perfect hunter.
In Lord of the Clans, Durotan is able to make out the sound of an assassin drawing his blade through the sound of a busy river next to him, meaning they have really acute hearing.
In A Good War, Saurfang is able to smell a drop of blood that Nathanos had cleaned poorly off his blade. Nathanos was standing in the lower floor of a tower with his blade in sheathe – and Saurfang could smell the drop of blood through his sleep, waking up instantly.
Rise of the Horde goes to detail the eyesight of orcs during Durotan and Draka’s courting hunt. With their keen eyesight, they could easily study the depth and gait of the animal prints they were following without stopping for long to study them. They were analyzing the tracks on the fly.
In Lord of the Clans, Thrall demonstrates his strength being immensely greater than a fully grown human’s when he himself is still an adolescent. Their skin is described as “hide” and it’s thick enough to blunt the pain from a human soldier putting all his weight behind the punch. The tip of a spear being pricked at Thrall’s back barely even drew blood, let alone feel any pain.
In Beyond the Dark Portal, it’s established that because orcs have such a high pain threshold, conventional torture methods are useless on them. Turalyon has to enslave an orc with the Light before it offers any answers.
So orcs have established senses far greater than that of humans and they’re naturally much stronger, on par with I would say gorillas who are deceitfully strong.
On top of that, orcs share our own basic human physiology in terms of our hips which makes us very energy efficient attrition hunters, making us able to outlast literally any other animal on the planet. Because while most animals will out run us short distance, we will always outlast them long distance. Their bodies aren’t as energy efficient, meaning they exhaust themselves quickly. The beauty of attrition hunting is that you never allow the prey a chance to rest. You’re always there, looming over their shoulders until they’re too exhausted to offer a fight back.
Orcs are the perfect race of hunters. It’s no wonder that their courting ritual involves a hunt and clans like Frostwolves, Whiteclaws and Thunderlords were traditionally hunters by trade.
EDIT: Thanks to Manata, here’s a bit from Lord of the Clans regarding orcish night vision.
“Retreat!” he cried, and made for the pile of still-hot rocks that had once been imprisoning walls and the sweet darkness of the night. His clansmen followed. There were one or two guards who gave chase, but the orcs were faster and soon outdistanced them.
The agreed-upon meeting place was an ancient pile of standing stones. The night was dark, but orcish eyes did not need the moons’ illumination to see. By the time Thrall reached the site, dozens of orcs were huddled by the eight towering stones.
“Success!” cried a voice at Thrall’s right. He turned to see Doomhammer, his black plate armor shiny
- Lord of the Clans, page 87