X-Death Goes Down Easy!
Mix (via Chemist) Maiden's Kiss and Holy Water to make Kiss of Blessing. Give it to X-Death to kill him instantly and skip having to fight Neo X-Death, taking you straight to the ending!
In World 2's Kelb town, enter the Inn. You'll find a man sitting on a table. Talk to him, then sit on the chair on the LEFT (NOT in front of the man)! He'll give you some kind of wine then he'll give you an after meal gift of 8 Potions! You can repeat this over and over to get more Potions!