Cosmic Wayfarer

You are not of this planet, or rather any planet, you belong in the stars like either your progenitor, the cloud of ethereal mass that passed by you granting you magic or simply your own destiny that is inter written within the stars has foretold. 

Dastardly Spellcaster

At 1st level you have taken a liking to spell combat enough to master it. When you cast a cantrip as an action you can use your bonus action to make a weapon attack. In addition when you roll initiative you can quickly cast a cantrip that normally has the casting time of an action as a reaction.

Ace Helmsman

Also at 1st level you have a natural affinity to piloting Spelljammer Helms, when you link to a Spelljammer Helm you can pilot it by expending spell slots into the helm to make maneuvers or you can use sorcery points. While a link is created you can then exit the helm and still control the Spelljammer, you can even attack and cast cantrips while a link is connected however the second you cast a spell that consumes a spellslot you break the connection.

When you reach 14th level casting spell slots no higher than 3rd level will not break the connection to the helm.

Plane-Hopper

At 6th level you gain the ability to hop from point to point as you manipulate space itself. You can use a bonus action to teleport 60ft from you in any direction. you can use this ability a number of times equal to your Charisma modifier (minimum of 1) and get them all back on a long rest.

Living Realmspace

At 14th level you gain the ability to unleash your cosmic ancestry. As a bonus action, you can spend 1 or more sorcery points to magically transform your body for 10 minutes. For each sorcery point you spend, you can gain one of the following benefits of your choice, the effects of which last until the transformation ends:

• You gain a flying speed of 60ft and you can hover.
• You can breathe and speak normally in environments without oxygen.
• You can summon the power of the stars giving all your weapon attacks and damaging cantrips an additional 1d8 [damage]radiant[/damage] damage.
• You gain an AC bonus equal to your Charisma modifier.
• You can summon the power of a black hole allowing yourself to pull any enemies in a 30ft radius from you, towards you by 30ft with a bonus action.
• Whenever you are hit with a melee weapon attack the enemy takes radiant damage equal to your Charisma modifier + your proficiency bonus.

You can decide how each of your transformations look, you can have them simply be shimmering cosmic lights dancing around you or even your entire body suddenly looking like a starry night sky.

Intertwined Soul

At 18th level while you are linked to a Spelljammer, having 0 hit points doesn’t knock you unconscious. You still must make death saving throws, and you suffer the normal effects of taking damage while at 0 hit points. However, if you would die due to failing death saving throws, you don’t die until your link ends, and you die then only if you still have 0 hit points.

While in this form you can cast spells requiring a spell slot of 3 or higher however any spell slot above 3rd you must roll a Constitution saving throw of 5 + the spell slot level, on a failure your link ends and you die.