After winning the fight in the ARENA in SLUMTOWN you find a machine that lets you bet on fight in the Arena. With a little patience (not too much, but saving often is advisable) you can earn a lot of cash (500.000 should be quite sufficient), usually by betting on Mongo. When you get to the City later on you can be all the guns and ammo you might need, as well as several hundred REGEN PAKs and ARMORSEALs. Another Hint: The ELECTROSCISM Power (F2-F2) is great for killing just about anybody (especially gennos), it might take a couple of shots, but when the enemy is hit, he can't shoot back!

Edit file save00x.dat with a hex editor and you can change the following offsets:

0x6ac - unsigned word of current mana
0x6ae - unsigned word of maximum mana
0x318b4 - unsigned word of current health
0x318b6 - unsigned word of maximum health

0x3189c
0x3189e > - unsigned word, left armors current values
0x318a0

0x318a2
0x318a4 > - unsigned word, right armors current values
0x318a6

0x318a8
0x318aa > - unsigned word, left armors maximum values
0x318ac

0x318ae
0x318b0 > - unsigned word, right armors maximum values
0x318b2

change ^^^ values to E7 03 - it's 999 points