Final Fantasy VII/Materia

Strategy and challenges
Mastering every materia in Final Fantasy 7 would need a extremely long time. Still, mastering all the materia of the same color allows to get the extremely rare and valuable Master Materias.

Therefore, a player might choose to focus on one or two materia colors, and play through the game three times to get one Master Materia each time. Here is an example of a strategy:
 * Game 1: Green Materia: use the 21 Green Materia, plus the blue All materia and the yellow W-Magic materia, that can be used only associated with Green Materias; 24 different materias.
 * Game 2: Red and Blue Materia: use the 16 Red Materia and 11 Blue Materias (excluding the two that are incompatible with the Red), plus the yellow W-Summon materia; most of the Red Materias simply damage the enemies, therefore the Blue ones will give some variety to the game; 28 different materias.
 * Game 3: Yellow and Purple Materia: use 11 Yellow Materias (excluding the aforementioned W-Magic and W-Summon), the 17 Purple Materias and the blue Counter materia, that can be used only associated with Yellow Materias; 29 different materias.

Note that the purple Chocobo Lure materia is necessary to get past one step of the game and to obtain some rare materias; also, the purple Enemy Lure materia allows to speed up the growth of the materias.