We will make and animate a ‘Metaman’ character made from 'metaballs' that have the unusual property that they attract one another, causing their shapes to deform. 

To do a 3D animation there are 4 steps:

1. Make the body.

2. Make a skeleton or ‘armature’. This is called ‘rigging’.

3. Attach the body to the skeleton (this is called ‘binding’ or ‘skinning’).

4. Make the character move (this is called ‘animation’).

Here is a 10 minute video explaining the whole process - the video is probably clearer than the text instructions which follow. If you wish to download the video then I recommend that you download the the FLV (Flash video) version (right-click and choose 'Save target as...') which you can then play in the free FLV Player, for example (Google search!).

Step 1: Make the body

Switch to Front Ortho view (Numpad 1) and make sure you are in Object Mode and that the 3D cursor is at the origin (press Shift-C to move the cursor to the origin if necessary).

Add a metaball (Add>Metaball>Metaball).

Duplicate the metaball with Shift-D and drag the new metaball above the old one to make head (left-click to confirm).

Continue duplicating and moving until you have this shape made of 11 metaballs:

Save your work carefully in your own space (save very often!)

Step 2: Make the armature

In Front Ortho view and object mode, left-click where the body’s belly button would be to place the 3D cursor there. Switch to a different view (e.g. top view, Numpad 7) and make sure the cursor is correctly placed in this view too (it is not enough to look at only one view to know the real location of an object in 3D space). Switch back to Front Ortho view. Add an armature (Add>Armature). The armature is probably not visible since it is hidden inside Metaman’s body but it IS selected. At the top of the Properties window at the right of your screen choose the object button (a cube) and scroll down until you can see the X-ray option, which you should turn on for this bone. This makes the bone always visible even if it is behind or inside another object (as long as that object does not also have its X-ray option turned on).

Switch to Edit mode by pressing the Tab key or by selecting Edit mode at the bottom left of the 3D window. Right–click the tip of the bone to select it then press G and move the tip of the bone up to the level of the neck. Left-click to confirm this placement. Press E and extrude a new bone to the centre of the head.

Before doing the bones in an arm, first make sure you are still in Edit mode otherwise you will be creating bones as a different object. We want all our bones to be parts of a single object. Left-click in the centre of either shoulder to place the 3D cursor there and switch to a different view (top view) to ensure that the cursor is correctly places in 3D space. Switch back to Front Ortho view and add an armature (Add>Armature) as previously. The new bone will be created pointing upwards and you will be put into Object mode. Press Tab to get back into Edit mode – the tip of the new bone should be selected. Press G and move the tip of the bone to the elbow as shown. Press E to extrude a new bone and place its tip in the centre of the forearm as shown. Continue adding bones until you have the complete armature of 11 bones as shown below.

Notice the small bone under the main spine bone. This bone needs to be present so that later the leg bones can be ‘parented’ to this small bone. To place this small bone first (in Edit mode) select the root of the main spine bone then extrude (E) the new bone downwards. 

To finish making the armature we will ‘parent’ each inner limb bone to a spine bone. Note that if an object A is 'parented' to an object B then A becomes the child of B. A child can move independently of its parent but if the parent moves then the child follows. Start by selecting the left upper arm bone (Metaman’s left bones appear at your right since Metaman is facing you). Then hold down the Shift key and select the main spine bone (holding down Shift allows you to select multiple objects simultaneously). Open the parenting menu with Ctrl-P and choose to parent the ball to the

Place the 3D cursor in a shoulder and add another bone. Position and scale as shown, then continue adding bones until each limb has two bones as shown below.

Some of the bones have 'rolled' a bit and this can cause problems later. To remove the roll press A to select all the bones (you might have to press A more than once) then Ctrl-N and 'Z-axis up' to remove the roll.

Now we will 'parent' the limb bones to the spine bones. Select an upper arm bone, then hold down the Shift key and simultaneously select the main spine bone. Press Ctrl-P and choose to keep the offset (the gap). The arm bone is now the 'child' of the spine bone 'parent'.

Parent the other arm to the main spine bone and then the two legs to the small bone at the bottom of the spine. I selected both upper leg bones and parented them both to the small bone at the same time.

Step 3: Attach the body to the armature

In step 3, 'skinning' we will parent each metaball to its corresponding bone. Switch to Pose mode and select a metaball by clicking the ring that surrounds it (not the ball itself).

Hold down the Shift key and add the bone to the selection, then press Ctrl-P and parent the ball to the bone.

In the same way, parent each of the 11 balls to the corresponding bones.

Try rotating (press R) each bone to check that every ball is parented correctly. The balls (the 'children') should move with their corresponding bones (the 'parents'). Instead of confirming these rotations with the left mouse button, cancel them by pressing the Esc key or the right mouse button.

Step 4: Do the animation

We will store this pose in frame 1 of the timeline. Make sure that the timeline window shows that frame 1 is selected then select all bones (A) in Pose mode and insert a keyframe in frame 1 to record the location, rotation and scale (LocRotScale) of the bones. To insert a keyframe press 'I' or use the keyframe 'Insert' button in the toolbox.

Now click frame 40 in the timeline - this is where we will set the next pose. Select a bone and rotate it (R) and then repeat this for several other bones until the new pose is set. Switch to other standard views if necessary.

I also translated the whole armature upwards by selecting all the bones and pressing G. Insert a LocRotScale keyframe with all bones selected when your new pose is finished.

Select frame 80, make a new pose and insert a LocRotScale keyframe with all bones selected.

Try 'scrubbing' through the animation (drag the frame marker back and forth). For a smoothly repeating animation, we will copy the frame 1 pose to frame 120. Return to frame 1 and use the copy button in the tool box to copy the pose. Then go to frame 120 and paste the pose. Insert a LocRotScale keyframe with all bones selected.