That meaning, what game engine are you building your model to work with? Does it require to be Triangulated? What's your polycount limit? And, yes, you do have a limit. Even powerful machines like the PS2 and X-Box have to have polylimits for their models. With that said, let's get started. For this project, I've been told that we want to build pretty high with a limit of 3500, but I'm going to give myself a limit of 2000 triangulated faces, and then add the detail to work up to 3500. I've worked on projects before where the models had to be 800, 600, even 500 Tris. It's a challenge to say the least, and I would recomend it to any aspiring game artist. To the tutorial!

First, I get my drawings set up. This project is for an online game I've been freelanced to work for. I have a front, side, and back view thanks to an awesome concept artist. (Fig 1)
To get started, I'll create a cube and place it about in the center of the character's torso. (Fig 2) I'll then extrude it and reshape the vertices to roughly correspond to my drawing. (Fig 3) Doesn't look like much yet..
One trick that I was taught by a good buddy of mine was instead of using the X-Ray feature of maya in order to see your sketch behind your model, simply give your model a slightly transparent shader. You can even go so far as to add a SetDrivenKey slider to raise and lower the transparancy of the shader. Also, note that its almost impossible for an artist to draw both halves of a sketch perfectly symetrical. You'll notice how my model most fits the left side of the drawing. Pick a side that you want to adhere to and go with it. Later, you can add little asymetrical details, if you wish. Anyway, right now, the torso is quite flat looking (Fig 4). To add a little depth, grab all of the edges in front, back, and both sides and subdivide them once. Edit Polygons > Subdivide > Options. Grab the new vertices and scale them out. (Fig 5)
Next, grab the Split Poly Tool [Edit Polygons > Split Polygon Tool], and split along these new vertices. Then, soften all the edges [Edit Polygons > Normals > Soften/Harden > Options](Fig 6)
Then, I'll adjust vertices as much as I can, trying to get the model to fit the drawing. I'll use the Subdivide tool often. Finally, I'll Triangulate the model [Polygons > Triangulate] (Fig 7) Obviously, I still have quite a bit of tweaking...
Now, I'll cut the body in two, deleting the side that I was not trying to get exactly, and deleting the faces of the waist and neck. (Fig 8)
Next, I'll go about cleaning this mess up. One tool that will save your bacon is the Flip Triangle Edge tool [Edit Polygons > Flip Triangle Edge]. To use it, select an edge, hit the tool, and the edge flips direction. You'd be amazed how many times this will fix a sticky situation. Another one is Snap to Point (simply hold the "V" key) and Merge Vertices [Edit Polygons > Merge Vertices > Options]. What I usually do, is snap a point I feel like merging to another and merging it together using a .0001 distance in the options. A Lattice can also be used if you feel that you need to change the overall shape of the object. [Animation - Deform > Create Lattice](Fig 9)
To create the lip of the shirt at the bottom, I used the Extrude Edge Tool (Edit Polygons > Extrude Edge). It works the same way as the Extrude Face tool. Now, I'll try doing the head. To begin with, I'll create a sphere with 6 subdivisions along axis and height and position as in Fig 10.
Now obviously, my character's head is a bit different than the normal Joe, so this part of the tutorial may not help you all that much, but maybe you'll find it interesting if nothing else. Anyway, I'll now push and pull Vertices, split, merge, and flip to get the shape of the head. (Fig 11) Extrude and tweak (ie. push/pull vertex, split, merge, etc.) to extend the next and ears and always get used to tweaking the rest of the model. You'll probably notice quite a bit of small subtle differences in the torso and head throughout the rest of this tutorial, but I won't touch on actually doing the changes unless they are major and introduce a new tool. (Fig 12)
Right now, I'm not going to add little details to the head such as eye sockets and nostrils, because I have a self-inflicted polycount limit of 2000 and I'm not even half done with the model not to mention this model has fairly large wings. However, I'm going to give myself about 500 or so extra polys for the wings alone. The 2000 is just for the main character since the majority of your character models you make for a game won't have wings (unless your doing some sort of bird game...;) What I'll do is complete the model and see how much leeway I have in my polycount. For example, if I fully complete his body with 2500 polys, I'll go back and add little details such as eyes and nostrils, etc. until I hit that magic number of 3500.
However, one thing that is going to be required for the animation of this models head is an opening and closing beak. So let's go through that next. First, I'll select all of the faces that are going to cause the beak to open. (Fig 13) Now, I'll use the Extract Tool (Edit Polygons > Extract). Make sure after you do this, you turn on Keep Faces Together at the bottom of the Channel Box. (Fig 14) What this tool does, is detach the selected faces from the rest of the object, creating a new polygonal object.
Next, I'll take this new object, move the pivot to the jaw and rotate it open. Now because I want to control the opening of the character's jaw with bones, I'm going to reattach it to the head, but this last step has opened the hole of the character's mouth in order to model the mouth's interior. Now, when the creature screeches at the player, we're going to see its gullet in all of its yucky splendor! (Fig 15) You could even add a tongue! I might, but I'll wait until I see if I have the polys for it... Right now, I'm at 600.(Fig 16)
Time for the arms. Now, my character has large shoulder pads, so I'm going to model the arms seperate from the rest of the body. For a character without any sort of division between shoulder and arm, you may want to just extrude the arm from the torso. Also, it's an industry standard to model your character's arms either stretched out to the side or extended away from the body about a 45 degree angle. This is to help in the character setup stage when you add an skeleton and weights to your joints. For my birdman's arms, I'll start with a cylinder with 6 subdivisions axis and 0 subdivisions caps. Extrude and rotate the arm down and merge to create a clean rotation joint where the shoulder meets the arm. (Fig 17)
Now for my character, both arms aren't exactly the same. The character's left side has a long sleeve, while the right has a short sleeve. So, although I haven't done much yet, I'll go ahead and duplicate the joint to the other side. Now I have a good starting place for each side. [NOTE: Always be mindful of your normals when duplicating and mirroring geometry.]
From here, I'll extrude and tweak to create the arm. Take note how my elbow is configured. (Fig 18) You'll notice that the V of the edges come together at the inner elbow. This allows a tight bend in the interior of the arm, while the exterior elbow can expand. (Thanks, Jeff! :)
Here's one thing you can do to help a little bit with the polycounts. The sleeve of my character stops about halfway down the bicep. Now, because the arm obviously isn't going to bend at this point, I can extract the rest of the arm parent them together. See the figures to see what I'm talking about. :) Fig 19, Fig 20, and Fig 21.
Now, I'll do the character's Left Arm. It's done in the same fashion as the other one. First I'll extrude (Fig 22) and Tweak (Fig 23), again using the "V" elbow.
I'm going to bypass the hands just yet. For a lot of game engines, things like weapons and other hand-held items for the character will be modeled with the hands attached. So, now, let's go for the legs. First, I'll create a 6 subdivisions cylinder and position it. Again, extrude and tweak. (Fig 24)
Now, duplicate and mirror the leg (remember: NORMALS!)
Use Extrude Edge and the Append to Polygon Tool [Polygons > Append to Polygon Tool] to create the section of the pelvis between the two legs. (Fig 25)
For the feet, simply grab the ring of edges around the ankle and Extrude Edge downward, Subdivide, Push/Pull points, Append, etc. to create the foot. (Fig 26 and 27)
To create the claws, I'll grab some polygon cones, reshape and place them, and use the Append tool to connect it to the main foot. (Fig 28)
Now, for the extra feature of this character... the wings! Now, obviously, much like his head, this part of the tutorial may not be as useful to those of you trying to model a soccar mom character, but maybe you'll find it interesting. :)
Anyway, I'll first start with a small 6 subdivision cylinder at the shoulderblade where the wing will begin to come from. I'll then extrude the cylinder a few times to create the ridge of the wing. (Fig 29)
Because eventually this wing will be animated expanding and contracting, I'm going to model it stretched out a little more than seen in the drawing in order to help with the animation process down the line. So, with that in mind, I'll continue to extrude, beginning to slightly taper the ridge of the wing as I get closer to the tip. After a little more tweaking, I'll extrude the edges running along the bottom of the ridge to start the actual wingspan.(Fig 30)
Obviously, this doesn't look all that great at the moment. But after about a half hour or so of diligent tweaking, you can get what you need. (Fig 31)
Now, let's attach the stalk of the wing to the back. First, select the faces in the section to make the joining area. What I'm going to do is model the actual hole in the armor that the wing is protruding from, so after selecting these faces, extrude and scale into the body. (Fig 32)
Delete the last tier of faces, creating the hole. (Fig 33) Next, I'll move and snap/merge the end of the wing to the new opening. (Fig 34)
At this point, besides the hands, I've pretty much got his entire body done with 1800 faces. (Fig 35) I'll now go back and start adding little details such as more muscle definition, armor details, eyes and other facial features, etc. Eventually, I have the complete model using 3500 faces.
You'll probably notice that a lot of this tutorial was using pretty much the same tools over and over. It can really be helpful to create custom shortcuts in the shelf bar like I've got in Fig 36. To create one, very simply hold Ctrl+Shift and select a tool in your menu system. A small icon for that tool should appear on the shelf.

Hopefully this has given you a better idea about game modeling. Let me know what you think!

Michael McKinley