Firstly apologies as the example I gave above was using Cycles nodes instead of using Blender Internal which you were using in your morph blend. The Diffuse BSDF, Mix Shader and Material Output are Cycles nodes thats why you couldn't find them in BI.

Secondly the example I showed above (Cycles or BI) was showing Shader nodes where as the image you posted above is showing Compositor nodes.

I am also wondering if the effect you are after is actually intended as a "Fade" which would be better suited using either Blenders video editor or another video editing program?

Fade In / Fade Out Tutorial

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