Singed Stuffing Scroll is very cheap and good to use. Other scrolls that would be handy are expensive (5m+) so you can equip that and use it every turn and it will be effective. Azathoth Curled Bow, Azathoth Spiny Gauntlets, Poisonous Azathoth Tentacle. If you buy those 3 weapons and have them in your set at the same time they all get stronger. All together under 1m sP. Use the Bow / Gauntlets for damage, Tentacle for slightly less damage but a 6% heal. Modifying is easy and worth it. The ones in the battle shop are only some of the options. I think Parched Tear Crystal is a cheap one to use and almost the best. It adds some damage and has a chance of activating a blessing that makes you immune from getting frozen. You might as well equip them to everything you can. To do that you can click on the crystal through your inventory, or have them in your inventory and go to your armory and "Click here to modify your weapons."

Those weapons will do a lot of damage but you'll find yourself getting low in health very quickly. One weapon you should save up for is the Phoenix Quill. Expensive but you will use it forever. It heals your health fully once per battle. if you have a bit of extra sP to spend after the other suggestions Replica Minotaur Knocker would be a good addition (~5m)

oh thank you! i bought the scroll and the Azathoth items. i also modified all the weapons with the parched tear crystal. for a weapon that has two modification slots, what do you recommend for the second slot? also will the azathoth items still become stronger if i have other things in my default weapon set?

You can use a second parched tear crystal and it won't hurt, or if you want variety then a singed tear crystal is good too. Does slightly more damage and has a chance of activating a curse on your opponent. As long as you have all 3 at once in there that is as strong as they will be.

thank you very much. i'm doing 400+ damage now instead of 100+. that's too awesome.