[This is for v55]
This is very useful in private servers. Others won't see you hit 20 times, but you will. The damage will count as if you hit 20 times, when you are actually only hitting once. Ownage in PvP as well =D
Multiple Attack Hack:
Replace the the Skill.wz in your maplestory folder with mines.
This hack lets you hit 20 times per multiple attack skill. So, you would throw 20 stars per throw with Lucky Seven(only uses 1 star). Also for Magic Claw, Savage Blow, Double Stab... etc..
-867 Downloads
Equip Hack with Unlimited Mana:
Lets you wear items regardless of level requirement or job.
Also includes unlimited mana(mana still drains to 0 but you can still keep on using skills.)
-740 downloads
Update 6/22/09: Tested and still working :]
All credits go to LilAznBoi at GzP.