Bastion's Thunderous Field

Grasping the bottle of thunder in your hands a thunderous field of energy envelops you granting you additional effects to your movement.  Upon casting, choose a destination up to your speed and immediately run to this location.  You gain no additional speed from this spell & no creature may be targeted more than once per casting.  During your movement, any provoked attacks of opportunity are made at disadvantage due to the thunderous field of energy encasing you.  Each creature that you pass within 5 feet along your path must make a Dexterity saving throw.  On a failed save they suffer 2d8 thunder damage or half as much on a successful save.  In addition, creatures that fail the save will take an additional 1d8 thunder damage if they take any action, including moving during their next turn.  

Upon stopping movement, the field discharges and dissipates causing a thunderous boom that can be heard for 100 feet per level of spell slot used to cast the spell before attempting to return to the bottle.  If the bottle is magical, the sound becomes re-contained, otherwise, the component is lost in the casting.

If cast at a higher level, the thunderous field grants you an additional 15ft of movement OR changes the disadvantage to opportunity attacks to no longer provoking them at all during the movement of the spell.