Replace a 1 with an I in POKE function ... 
 -  POKE&H68F+I,ASC(MID$(A$,1  <--- that 1 should be an I

Full function
760 FORI=4TOH:DEFSPRITEI,(3+(R=11),1,-(PEEK(&H481)=1ANDR>5),-(X>TX ANDP<2),0)="":NEXT:FORI=1TOLEN(A$):POKE&H68F+I,ASC(MID$(A$,I-(X>TX ANDI MOD2=1ANDP<2)+(X>TX ANDI MOD2=0ANDP<2),1)):NEXT:K=SGN(X-TX)



-----------------


--------------------
Tracking Hit Points
--------------------
  - HP = your current HP
  - HI = you max HP
  - TH = enemy HP
  - A = Sword level (inverse, 5 = 1)
  - B = Armor level
  - P = Monster type (0-3)
  - R = Room # 

910 DATA"0512121267"
  0=Penguin with door
  1=Red Woman with door
  2=Tektite with door
  3=Flashing Space Man with door
  4=Penguin no door
  5=Red Woman no door
  6=Tektite no door
  7=Flashing Space Man no door
  8=Crash and Error

100 RESTORE910:READA$:P=VAL(MID$(A$,R,1)):IFP>3P=P-4:PALETB 3,13,13,13,13
  - Reads in P from the 910 DATA and pulls out enemy info (door or not)

120 TH=-(P=1)*200-(P=2)*500-(P=3)*15000+R*R*100:IFPEEK(&H47F+R)=0TH=0TY=0
  - R=Room #
  - Room 1, Boss 0 1*1*100 = 100 takes 5 hits
  - Room 2, Boss 1 -1*200+2*2*100 = 200 takes 20+ hits

850 HP=HP-TH/B
860 HP=HP-P*10
   - Damage taken

870 GOSUB990:TH=TH-HI/A:TX=TX+(P<>3ANDTX>20ANDTX<224)*K*8:IFTH<1POKE&H400C,3,0,138,0:TH=0:TY=0:FORI=4TO7:SPRITEI:NEXT:HP=HI:GOSUB580:RETURN150
   - hitting the enemy takes off YourMaxHP/(Inverse Weapon) so YourMaxHP*Weapon