Difference between GBM and MBM

Before definition of MBM (Medial Black Magic) all MBM was called GBM (Greater Black Magic), so it can bring some confusion between the two.

In Black Magic Book of Aquino, Medial Black Magic, is discussed as follows:

" It is easy to focus strongly and exclusively on either one or the other of these two categories, so much so that we miss that grey area wherein they blend. Let us call this Medial Black Magic (MBM).

MBM involved the use of the Magical Link in its simplest, most direct form in an operative context. Unlike LBM, in which the magician uses forces and features which are of the objective universe to accomplish his goal, MBM has similar goals but uses metaphysical means - the Magical Link - to realize them. It is not as "pure" as true GBM.
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The difference between GBM and MBM is a difference in intent. 
MBM plans to change the subjective universe to cause a change in the objective universe. 
GBM intends to change the subjective universe  to perceive oneself (own SU) or cause a change in the subjective universe, although it can cause an unintended change (good or bad depending on the perspective) in the objective universe through synchronism.

The final objectives of MBM and LBM are the same.