Peasants are the hardworking, loyal citizens of your nation. They can construct and repair any type of building you need and gather the resources to do so. Don't even think about making less than 15 or 20 before upgrading to keep, as that means more cash flow and more units. By the time you get to castle you should have at least 25 and preferably 30 or 35. Peasants are what can make or break your army, so make as many as possible! Cost:400 gold
Footmen are the earliest military unit you have available. They are no match for later units, but they can prevent you from losing the early game. I suggest having at least 9 or 10 of these guys before going to keep. Cost:600 gold
Elven Archers and later Rangers are masters of the bow, and can cast their bolts safely from a distance. While they are weak early on, fully upgraded Rangers can slaughter any threat from behind the front lines. I usually don't make too many in the early game but upgrade to rangers as soon as I get a keep. Since you should have enough footmen, be constantly making archers during the keep upgrade so they'll be there for use when you start making knights. Cost:500 gold,50 lumber
Knights represent the fiercest fighting force in Lordaeron. They ride upon great war-horses and crush all opposition with their war-hammers. The only stronger land unit available is the Paladin. Once you can make these guys, forget about footmen. Your army should be about one-third rangers and two-thirds knights/paladins. Cost:800 gold,100 lumber
Paladins are the holy men of your kingdom. They can ride into battle to lay their healing hands upon another, or disperse the undead with holy light. These should make up the majority of your fighting army, since they have the best weapons and armor available to a Human army. Cost:800 gold,100 lumber Upgrade:1000 gold Spells:1000 gold and 2000 gold
Mages are the strongest weapon Humans have-if used properly. Details are on the land strategies page.Cost:1200 gold
Ballistas are the hulking behemoth crank-bows of the Alliance. They can deal incredible amounts of damage. However, they are extremely slow (both to build and to move) and cannot attack units that are closer than a square or two to it. So they usually aren't worth it unless you need to break a wall-in and you don't yet have mages. Be sure to protect it with Knights or footmen. Cost:900 gold,500 lumber
Demo Squads can level large areas in a single blast. Though they must sacrifice themselves to accomplish this, they are stil valuable members of your army. Their blast does 400 damage to anything within one square of where they detonate. Cost:700 gold,250 lumber
Gnomish Flying Machines are the scouts of your army. I recommend building at least 6 or 7, enough to have the entrances to your base and your enemy's covered, and have a few for scouting. These should take priority over demo squads at first. Cost:500 gold,100 lumber
Gryphon Riders are expensive, take forever to build, and are killed easily. The only time I use them is in a stalemate, when the opponent has no air defense, and I need an edge. Even then, I try to take out the lumber mill with demo squads first. Usually gryphons aren't worth the cost. Cost:2500 gold