Magic-User Options: A Basic Fantasy Supplement

From the Introduction:

These optional rules are presented buffet-style for the GM to pick and choose among based on the needs and flavor of the campaign. Six different ways of combining options based on campaign style (close to core rules, dark fantasy, heroic fantasy, high magic, military fantasy, and Old School) are given in Appendix A. This supplement specifically avoids options which are the focus of other supplements such as 0-level spells (AKA cantrips) or Magic-User subclasses, though those supplements are listed in Appendix C. The terms Magic-User' and 'magician' are used interchangeably throughout this supplement for the sake of variety.