Prerequisite: Display of Heroism feat, proficient in Athletics and History, character level 7th.

Features

Hit Dice: 1d12 per monument of war level.

Hit Points: 1d12 (or 7) + your Constitution modifier per monument of war level.

Instant Boot Camp

As a bonus action you can shout directions you recall from your own military training. You and each ally who can see or hear you becomes proficient in Athletics and proficient in all simple and martial weapons for the next minute. You and each of those allies can immediately stand up or drop prone, then walk 10 feet or crawl 5 feet. Once you have used this feature, you cannot use it again until you finish a long rest .

Fearless Mien

Accounts of your heroism carry their own strength. You and allies within 30 feet of you have advantage on saving throws against being frightened . When you use your Display of Heroism , each ally you affect can spend and roll one hit die, and heal that many hit points. If they were at 0 hit points, they instead heal that much plus 1.

Shell Shock 

As an action you can call upon a powerful memory of being caught in an artillery barrage to conjure psychic manifestations of a cannon strike in your immediate vicinity. This manifestation must be centered on a space no more than 10 feet away, and strikes in a 15-foot-radius burst. Thus you must be caught in your own remembered blast, though perhaps cover might shield you.

Targets in the area take 7d6 points of force damage, and are pushed 5 feet and knocked prone. A successful Dexterity save (DC 8 + your proficiency modifier + your Constitution modifier) halves the damage and prevents a creature from falling prone. The area of the blast is filled with dust and smoke, providing concealment until the end of your next turn. After using this power, you cannot use it again until you take a short or long rest .

Do You Want to Live Forever? 

You have survived bullet hells or arrow tempests where the crossfire should have killed anyone, and that story is so well-known and powerful that it protects you. When you have no physical cover or concealment, you gain the benefit of three-quarters cover against ranged attacks.

Remembrance of the Heroic Sacrifice

You can call upon the psychic memory of a long-dead friend to save an ally from an attack. When an attack is about to hit you or an ally, you can conjure the psychic manifestation, who is struck by the attack instead of the original target. The manifestation is instantly destroyed, but the original target of the attack is unaffected by it.

After you use this ability, you cannot use it again until you complete a short or long rest .

Cannon Overture

When you use your shell shock ability, on the following two rounds you may as a bonus action call in additional artillery strikes. These strikes do not need to include you in their area of effect, but each one must land at least 30 feet from the center point of any other previous strike.

Most beasts, plants, many monstrosities, and even some undead creatures from the Monstrous Menagerie are appropriate for use and make excellent challenges for voidrunners. The list below contains a selection of non-spellcasting creatures which can be used without any changes.

Of course, if your universe contains magical and fantasy creatures, then the whole of the Monstrous Menagerie is a vital resource, and your voidrunners can battle dragons on alien planets and wizards on ancient space stations. Alternatively, magical creatures make for excellent ‘omnipotent’ beings or aliens with exotic powers–many science fiction franchises play with the idea of mythology as unexplained science. Perhaps lycanthropy is a known medical condition, a specter is a lingering psychic imprint, or ‘magic’ comes from another dimension.

Lore. Where a monster’s entry contains Arcana as a lore skill check, use Science instead.

Appearance. You may wish to alter a creature’s name or appearance from the standard Monstrous Menagerie entry–a T-rex may be some kind of fearsome alien lizard, and a wolf may have fangs and a hairless hide.

Magic vs. psionics. Magical abilities can be re-skinned as psionics.

Monsters usually encountered in space (those with a speed listed as Spacefaring Slow, Spacefaring Average, or Spacefaring Fast) are typically more powerful than terrestrial monsters of the same challenge rating. These cosmic threats are strong enough to match a party’s ship, not merely the party itself.

Spacefaring monsters of CR 3 and below have similar statistics to standard (non-spacefaring) monsters. For a battle in which a party must face a CR 4 or higher spacefaring monster without the benefit of a starship, triple the spacefaring monster’s XP and treat it as 3 standard monsters of its Challenge Rating for purposes of encounter building. For a battle in which a starship battles a CR 4 or higher standard monster, grant ⅓ of the monster’s XP and treat it as a monster of ⅓ its CR for the purposes of encounter building.