system
Given the following post, respond as if you're commenting on Reddit:
human
[Warcraft] What's the deal with these Orcs?

How many times did they try to invade and how many are waiting to come over and fight?
gpt
They only invaded once, and the majority of the species came over. After Warlock Magics accelerate the maturation of their young. A relatively small faction of Orcs remained behind under the command of the fallen Shaman, Ner'zhul, which was subsequently devastated by the Alliance Expedition led by Grand Marshal Turalyon. A few stragglers survived, along with the small city of Garadar in Nagrand.

There was a second invasion, caused by a bridging of alternate timelines by the rogue Bronze Dragon Kairosidormu, but that was notably less successful, and only amounted to a small percentage of the Orcish population before a counterattack cut them off.