Spellblade Mastery

You are an artful student of both warfare and the arcane arts, bolstering both capabilities when paired. You gain the following benefits: 

• While you are holding a martial weapon with which you are proficient, your spell save DC increases by 1. 
• While you are concentrating on a spell, your attack and damage rolls with martial weapons with which you are proficient recieve a bonus equal to 1. 
• You may use your bonus action to change the damage type dealt by a martial weapon you are holding. The new damage type must be choosen from among the damage types you can deal with your spells or cantrips. This effect lasts for 1 minute, and you must finish a short or long rest before using this option again.