Homebrew Adeptus Astartes Species Details

The Space Marines or Adeptus Astartes are foremost among the defenders of Humanity, the greatest of the Emperor of Mankind's warriors. They are barely Human at all, but superhuman; having been made superior in all respects to a normal man by a harsh regime of genetic modification, psycho-conditioning, and rigorous training.

Space Marines are untouched by plague or any natural disease and can suffer wounds that would kill a lesser being several times over, and live to fight again. Clad in ancient power armor and wielding the most potent weapons known to man, the Space Marines are terrifying foes and their devotion to the Emperor and the Imperium of Man is unyielding. They are the God-Emperor's Angels of Death, and they know no fear. 

Creating Your Character

At 1st level, you choose whether your character is a member of the Adeptus Astartes race.

When determining your character’s ability scores, increase one score by 2 and increase a different score by 1, or increase three different scores by 1. Follow this rule regardless of the method you use to determine the scores, such as rolling or point buy. The “Quick Build” section for your character’s class offers suggestions on which scores to increase. You can follow those suggestions or ignore them, but you can’t raise any of your scores above 20.

Languages

Your character can speak, read, and write Common and one other language that you and your DM agree is appropriate for the character. The Player’s Handbook offers a list of languages to choose from. The DM is free to modify that list for a campaign.

Creature Type

Every creature in D&D, including each player character, has a special tag in the rules that identifies the type of creature they are. Most player characters are of the Humanoid type, including the Adeptus Astartes. A race tells you what your character’s creature type is.

Here’s a list of the game’s creature types in alphabetical order: Aberration, Beast, Celestial, Construct, Dragon, Elemental, Fey, Fiend, Giant, Humanoid, Monstrosity, Ooze, Plant, Undead. These types don’t have rules themselves, but some rules in the game affect creatures of certain types in different ways. For example, the cure wounds spell doesn’t work on a Construct or an Undead.

Life Span

The typical life span of a player character in the D&D multiverse is about a century, assuming the character doesn’t meet a violent end on an adventure. Members of some races, such as dwarves, elves and Adeptus Astartes, can live for centuries. If typical members of a race can live longer than a century, that fact is mentioned in the race’s description.

Height and Weight

Player characters, regardless of race, typically fall into the same ranges of height and weight that humans have in our world. If you’d like to determine your character’s height or weight randomly, consult the Random Height and Weight table in the Player’s Handbook, and choose the row in the table that best represents the build you imagine for your character.

Adeptus Astartes height are around 7'5'', plus or minus 5''.

Ballance

This information is for the DMs that would like to introduce the Adeptus Astartes in their campaigns.
If any player in your game is playing any race other than an Adeptus Astartes, they should be able to select an extra feat or two and/or have access to a magical item (DM discretion) to balance out for the extra power of the Adeptus Astartes race.

Adeptus Astartes Traits

As a Adeptus Astartes, you have the following racial traits.

Creature Type

You are a Humanoid.

Size

You are Medium.

Speed

Your walking speed is 35 feet.

Astartes build

You have proficiency in the Athletics skill, and you count as one size larger when determining your carrying capacity and the weight you can push, drag, or lift.

Transhuman

You have immune to poison damage and you cannot be poisoned.

Astartes Organs

You can draw power from your Implants and strong body to shrug off harm. When you take damage, you can use your reaction to roll a 3d6. Add your Constitution modifier to the number rolled and reduce the damage by that total.

You can use this trait once per long rest.

Psycho-conditioning

You are immune to the Frightened condition.