some weapons have like options like slice (iffinity) i forgot ?.. what are the other ones and what weapons will benefit more from those?...is it like slice = axe? dual sword?.. what i dont know. kindly tell me some info on this

If you were ACTUALLY reading the guides here, you should roughly have knowledge about them. All weapons posses a certain metallic element when not infused with the natural elements.

Slice: Sword, Odachi, Twin Swords
Impact: Axe, Wand?(Normal attack?)
Pierce: Spear, Bow

Whether increasing these elements increase attack, defense, or both is still up for debate but meh, don't do it here.