Total War: Warhammer players will have loads of fun playing the Greenskins campaign. Here's a rough guide on how to fight like an Orc.
Maintain Fightiness At All Cost
Fightiness should be maintained at all cost since your army will fall apart if it drops below 20. You could keep it high by waging wars against anyone. Even simple raiding can keep it up. Maintain a Fightiness level of at least 80, a 17 sized or more army and you get a WAAGHHH!! To the initiated, the WAAGHHH!! is a 20 stack strong AI controlled army. You may not have direct control over them but can still unleash this ally to do your dirty works, according to Steam.
Pillaging And Looting Is the Best Policy
Greenskins are at their best when they pillage and loot. Don't bother keeping control of territories. In fact your army is more likely to lose its Fightiness if it's stationed in one place too long. If a conquered territory rebels, simply go back and put it down. You could also gain loots from those actions. Unlike other civilizations, the Orcish economy seems to be revolving around pillaging and looting.
Orcs Like Raids
As previously mentioned, Fightiness level goes down once your Orcs stops fighting. Maintain their fightiness by engaging in raids. You can also increase the recruitment level and get loot as well.
Confederation Is Good
Letting Other Orc factions to confederate with you is good since it increases your territory and army. It's also way better to side with factions near your territory for easier defense. You could also get the other Legendary Lords to join your side although their army contribution generally suffers from low fightiness.
Losing Battles Lowers Fightiness
Constant battles increase Fightiness but losing every time will lower it also. If the opposing army is too strong, you need to increase the size of your army or their Fightiness. Simply conducting raids or attacking weaker enemies in the meantime will help your maintain or increase its edge. The game is available in Steam.
