Skillz is one of your character's stats. Skillz is one of the two ways you can increase your character's basic attack, and upgrade your abilities by a percentage. You can save some time by buying Skillz upgrades at the shop.
Normal Sword: +8 to Skillz. Costs 220 Tix.
Bluesteel Blade: +24 to Skillz. Costs 400 Tix + Normal Sword.
Illumina: +60 to Skillz. Costs 540 Tix + Normal Sword + Bluesteel Blade.
Ghostwalker: +80 to Skillz. Activate to increase speed 20% for 5 seconds. Costs 600 Tix + Illumina.
Elemental Stone: +6 to Skillz and H4X. Costs 300 Tix.
Ancient Blade: +24 to Skillz and H4X. Costs 480 Tix + Elemental Stone + Elemental Stone.