Mariner

A veteran of marine engineering, as a Mariner you know how to keep your ship running in all seas.  Many voyages would have been lost at sea were it not for these skilled artificers keeping the ship in one piece for the long ride home. 

Sea Legs

With experience you have adapted to life at sea.  From third level you have advantage on all checks to swim or climb.  You also have advantage on any check or saving throw to deal with the effects of rough seas, this could include a dexterity check to walk in a straight line on a rolling deck or a constitution save to resist seasickness.  

You gain swimming and climbing speeds equal to your walking speed at your ninth level in artificer. 

Sailor's Skills

From level 3 your experience as a sailor grants you the following proficiencies: Water Vehicles, Navigator's Tools.  If you already have these proficiencies from the Sailor background then you may take proficiency in the Healer's Kit plus one artisan's tool or musical instrument of your choice.  

At Level 3 you gain proficiency with the Scimitar and the Net.  

At Level 8 you gain proficiency with the Glaive and all Crossbows.  

Mariner Spells

Starting at 3rd level, you always have certain spells prepared after you reach particular levels in this class, as shown in the Mariner Spells table. These spells count as artificer spells for you, but they don’t count against the number of artificer spells you prepare.

Level 3: Thunderwave, Healing Word 
Level 5: Find Traps, Warding Wind 
Level 9: Thunder Step, Tongues 
Level 13: Storm Sphere, Freedom of Movement 
Level 17: Steel Wind Strike, Mass Cure Wounds

Extra Attack

Starting at 5th level, you can attack twice, rather than once, whenever you take the Attack action on your turn.

Wether Eye

From level 5 your experience on the water has granted you a keen eye for the phenomena of the weather.  You know the natural weather for the current day and the next day.  If the weather is changed from this forecast by any kind of magical or supernatural or other means then you can make an intelligence check with proficiency to try to glean information on how and/or why the weather was changed.  

Old Salt

By level 9 you have spent what seems like a lifetime at sea.  Any tool (not a weapon) granted to you by the Sailor's Skills feature and/or by the Sailor background is considered an Artisan's Tool for the purposes of Tool Expertise. 

Long hours on night watches have made you hardy to the biting winds.  You have resistance to cold damage.  

Stormy Seas

Long exposure to seeing thunder and lightning on the high seas has given you a flash of inspiration.  Starting from your ninth level in artificer when you are hit with a melee attack you can cause your attacker and one other target you choose within your melee range to take 1d6 Lightning damage.  You can do this as many times as your intelligence modifier and regain all expended uses after a long rest.  This increases to 2d6 at level 13 and 3d6 at level 17.  

Steady As She Goes

Years aboard ship have given you an uncanny ability to move in rough conditions and to stay on your feet.  At level 15 you gain the following: 

You have advantage on checks and saving throws against being shoved or knocked prone.  

You gain a permanent +1 to AC. 

You gain an additional +1 to AC and advantage on checks and saving throws against being grappled when you are on a moving surface such as a ship's deck or a moving wagon.  

You can add your proficiency bonus to any attack by a vehicle-mounted weapon (such as a ship's ballista) operated by yourself or by NPC crew acting under your direct instruction.