Feature: Expert Spelljammer

You gain a number of spelljamming dice equal to your Spell Attack Bonus. While using a Spelljamming Helm that you are attuned to, you can expend spelljamming dice, which are d8s, to use a maneuver. Many maneuvers enhance your movement or an attack in some way. You can use only one maneuver for any movement, action, bonus action, or reaction. Maneuvers that require a saving throw will have a DC equal to your Spell Save DC. You regain all of your expended spelljamming dice when you finish a short or long rest.

Ambush. When you make an initiative roll, you can expend one spelljamming die and add the die to the roll, provided you aren't incapacitated.

Bash. While moving within 5 feet of a target ship, as an action you can expend one spelljamming die to smash laterally into the target ship. Both ships will take damage and gravity will shift normally. All creatures on both ships must make a Dexterity saving throw. Roll the spelljamming die and add the result to the saving throw of all creatures on the ship you control. All creatures that fail the saving throw will be knocked prone.

Brace. When you are attacked by a creature you can see, as a reaction you can expend one spelljamming die to brace your ship for attack. Roll the spelljamming die. Until the start of your next turn, your ship gains a bonus to Damage Threshold equal to the number rolled.

Broadside. While moving, as a bonus action, you can expend one spelljamming die to maneuver your ship so as to grant advantage to all of your ship's attacks against a target ship of your choice.

Cast a Spell. You can expend one spelljamming die to cast any spell you know and have prepared from any point you can see from on your ship as though you were stood there. Any spell that has a target of Self can be cast on the ship as a whole.

Dash. As an action, you can expend one spelljamming die to dash a distance equal to 5 times the roll, in feet. If the distance dashed is less than your ship's base speed you can spend a bonus action to travel an additional distance equal to the previous dash. When you use a bonus action in this way your ship's Damage Threshold is decreased by a value equal to your roll until the end of a turn in which you do not use this dash maneuver. This effect can stack with subsequent bonus action dashes.

Evasive Maneuvers. When you move, you can expend one spelljamming die, rolling the die and adding the number rolled to your ship's AC until you stop moving. Your ship is considered moving until it ends a turn without moving at least all of its base movement speed.

Gravity Warp. When you make contact with a ship that weighs more than yours and your gravitational plane shifts, you can use a reaction to expend one spelljamming die and add 10 times the roll, in tons, to your effective weight until the start of your next turn.

Ram. When you move, as an action, you can expend one spelljamming die to dash into another ship. This maneuver bypasses any damage threshold and deals damage proportional to the number of spaces you moved before making contact. Your ship suffers damage normally.