Doomtrain's Forbid Med-RF can be used to make stat boosting items, but what items are they?
With Tonberry's Familiar command and Eden's GFAbl Med-RF, you can buy items to make HP, Str, Vit, Mag, and Spr Ups from the Esthar Pet Shop:
10 Giant's Rings > 1 Gaea's Ring > 1 HP Up
100 Power Wrists > 10 Hyper Wrists > 1 Str Up
500 Vit-J Scrolls > 50 Orihalcons > 5 Adamantines > 1 Vit Up
100 Hypno Crowns > 10 Royal Crowns > 1 Mag Up
100 Force Armlets > 10 Magic Armlets > 1 Spr Up
Getting enough money for the items is time-consuming, but not hard. Just use the Quick Money trick above. If you have a lot of patience, you can max out all the main stats without Junctions.
Speed Ups & Luck Ups:
100 Cactus Thorns > 1 Hundred Needles > 1 Spd Up
100 Curse Spikes > 1 Dark Matter > 1 Luck-J Scroll > 1 Luck Up
Cactus Thorns can be won from Cactaurs. Use GFAbl Med-RF to turn 100 Cactus Thorns into a Hundred Needles, then use Forbid Med-RF to make that into a Speed up.
Curse Spikes are tough to stock up on. Tri-Faces are the easiest enemies to get them from, but they're rare. Anyways, use Tool-RF to make 100 of them into a Dark Matter; Siren must be Level 100 to do this. Then use GFAbl Med-RF to make the Dark Matter into a Luck-J scroll, and finally a Luck Up with Forbid Med-RF.