How to merge/morph/transform an object into another object in Blender?

Question

The letter "A" is walking from left to right and slowly evolves into the letter "B".

How is this done?

Here's my search process:

1. "Blender merge one rig into another" returned articles on how to combine various armatures.
2. "Morph blender character in timeline" returned a beautiful answer merging one object smoothly into another while animating but I need one object to 'disappear' completely into the other object over time.
3. "How to transform a moving object into another form in blender" returns searches about copying and duplicating objects.
4. "How to merge two moving objects in blender" returns articles on combining objects into a single object, like building a Transformer.

Most reference shape keys and target morphs, but will these work with complex objects? Or simple objects only?

e.g. Could a white rabbit run across a field and change into a blue duck?

I am new to Blender, so if I'm not asking the right question or using the right terms or if there's a better way to ask this question, I'd be happy to be pointed in the right direction.

Answer 1

Took a while, but found the answer watching an Olav3D Tutorial on Transformation Animations:

Basic Steps:

1. Add two objects (Object A [Default Cube] and Object B [Suzanne])
2. Add shrinkwrap modifier to Suzanne, select target--> Default Cube
3. Apply shrinkwrap modifier as shape key
4. In Object Data Properties Panel, edit shrinkwrap shape key: Increase shrinkwrap value to 1.0 (this shrinks it down to default cube size)
5. Click "i" to insert keyframe
6. Go to frame 100
7. Decrease shrinkwrap to zero
8. Click "i" to insert another keyframe
9. Set up camera and add materials, background, and lighting to taste
10. Edit render output settings (resolution quality, render samples, etc) to taste
11. If adding a material to Suzanne, add it to the default cube as well
12. Change render end frame to 130
13. Change file format output from PNG to AVI JPEG
14. Set render output quality to 100%
15. Render animation and voila! We're done, we successfully transformed(merged/morphed) Object-A into Object-B along the timeline.

Final Result (Better late than never!)