Increase the Learn Rate of Magic

Here's assassin's doc:
assassin17.brinkster.net/code2i.txt

I believe what you're looking for is at C2/6061.

Code:

Progress towards learning spell

C2/604B: F0 1F        BEQ $606C      (branch if no learn rate, i.e. no spell to learn)
C2/604D: EB           XBA
C2/604E: A5 FB        LDA $FB        (Magic points gained from the battle)
C2/6050: 20 81 47     JSR $4781      (Multiply by spell learn rate)
C2/6053: 85 EE        STA $EE        (Store this amount in $EE)
C2/6055: B1 F4        LDA ($F4),Y    (what % of spell is known)
C2/6057: C9 FF        CMP #$FF
C2/6059: F0 11        BEQ $606C      (Branch if spell already known)
C2/605B: 18           CLC
C2/605C: 65 EE        ADC $EE        (Add amount learned to % known for spell)
C2/605E: B0 04        BCS $6064
C2/6060: C9 64        CMP #$64
C2/6062: 90 02        BCC $6066      (branch if % known didn't reach 100)
C2/6064: A9 80        LDA #$80
C2/6066: 91 F4        STA ($F4),Y    (if it did, mark spell as just learned)
C2/6068: A5 F1        LDA $F1
C2/606A: 04 F0        TSB $F0        (tell Function C2/5D91 to enable gained Magic Point
                                     display, provided we've already gotten an Esper
                                     Magicite from Zozo)
C2/606C: 60           RTS