Versatile Spellstrike Feat 18
Source Pathfinder Secrets of Magic
Prerequisites Spellstrike
You can channel the entire realm of possibilities of your spellbook into an attack.
Once during your daily preparations, you can use a spell slot to hold that infinite potential, rather than using it to prepare a spell. When you make a Spellstrike, you can expend this special spell slot to immediately prepare and cast a spell from your spellbook at 2 levels lower than the slot's level. (As normal for preparing spells, you can use a spell of an even-lower level, heightening it accordingly.)
You don't have any spell prepared in that slot until you cast from that slot.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
MagusThis indicates abilities from the magus class.