basic rules summary

Ability Scores
STR: melee attack and damage, muscle check
CON: hit points, radiation/poison adjustment, resist trauma
DEX: defense, initiative, missile attack
INT: science skill, technical skill, languages
CHA: contact skill, reaction adjustment, subordinate morale
PSI: Psionic combat, PSI points recovery rate

Skills
Combat
Contact
Technical
Science

Classes
Command (Military): Leadership, Security, Fire Control
Science: Biology, Medical, Sentient Life
Operations (Technical): Communications, Navigation, Engineering
If choose no subclass, +10% to all XP earned
Enlisted Crew

Save Checks
Must roll higher than relevant save score.
Save scores are based on level, and do not vary by class.
Radiation/Poison: CON mod

Equipment
Entitled to Level +1 units at start.

Psionics
Use of any Psionic skill except Empathy requires a successful psionic combat against enemy.
Psi combat: Roll PSI score or less, add/subtract difference in PSI score of attacker/defender as penalty/bonus. If attack succeeds, the Psionic skill effect takes place.

Muscle Check
E.g. open door.
Roll 1d6, applying STR mod. 1-2 is success.

Search and Detect Checks
Base chance 1 on 1d6.

Foraging
Roll 1d6. 1 means find food for 1d6 people, or 1-2 succeeds for 1d6 people if stopping to focus on foraging.
There is a base chance that alien food is poisoned: meat 15%, fruit and plants 30%.

Surprise
1-2 on 1d6

Combat Sequence
1. Movement Declaration: Players declare character
movement or actions. The SM secretly decides alien
and NPC movement and action intentions.
2. Initiative: 1d6 is rolled by each opposing side.
3. Initiative winner acts first. The SM may check morale
for aliens or NPCs.
4. Movement is made.
5. Missile attack rolls are made, accounting for DEX
adjustments.
6. PSI powers are used.
7. Melee combat occurs; attack and damage rolls are
made, accounting for STR adjustments.
8. Other sides act through steps 4-7, in order of initiative
9. When all sides of a conflict have acted and the combat
will continue into the next round, the sequence begins
again at step 1.

Initiative
1d6 + DEX mod, rolled for each side by character in most danger.

Morale
Roll Morale Score or less on 2d6. Check morale when: ally killed, more than half of your side is killed or incapacitated

Attacks
Roll Combat skill or less on 1d20, plus STR mod for melee or DEX for missile, minus opponent’s DEX modifier, and armor if any. Add 1 if short range missile fire.
To reduce chances of being hit by missile fire, take cover: 25% cover -1, 50% -2, 75% -3, 75
% -4.
No dodge or parry option – might institute this in special cases like a Bat’leth duel.
20 is always a miss.

Damage
Per weapon.
1d2 for unarmed attacks. Death at 0 without medical intervention.

Armor
Imposes penalty to opponent’s Combat skill check equal to armor bonus.
Armor seems to have no disadvantages, and with such a deadly system, characters would have no reason not to wear them all the time.
Rules mod: skill check penalty equal to half the armor bonus.

Retreat
Fighting retreat: ½ move (20 feet)
Full retreat: full move, retreater forfeits attack this round and opponent gains +2 to attack.

Healing
1d3hp per day of rest, 1d6+1 with medkit (personal wound healer) used by a Medic or Scientific enlisted, 2d6 if attended by medic in sick bay, 2d3 if by Scientific enlisted man.

Ability Checks
Roll Ability or less on 1d20. Modifiers: +4 very easy, -4 very hard.

Ship Movement
Each warp factor equals a speed of 1 lightyear per day.

Transporter (Teleporter)
No check needed if being off by a meter or so wouldn’t matter. But if so, it is considered “blind” or “critical” and requires a Contact skill check. Failure equals destruction of beamed people or objects.
Beam back to ship automatically if in contact by communicator. If not, requires a Contact skill check, with failure meaning the wrong person or object is beamed back.

Ship Energy System
Ship actions and damage cost Power Pile Base (PPB).
If energy expenditure/damage exceeds PPB, the amount over is permanently subtracted from the ship’s PPB.
If reduced to double PPB, ship is destroyed.
Damage can be repaired by Engineering officers (level x3 PPB/day) and Operations enlisted men (level x2 PPB/day). All available Engineers and Operations enlisteds may be involved. Can only attempt this once between space stations.

Ship Combat
All ships fire simultaneously.
Can fire each of ship’s weapons once each turn
Roll Ship or less, once for each weapon fired. Ship roll depends entirely on range. Fire Control Officer adds +2, Operations Enlisted men adds +1
Phasers (beams) do 5d6 dmg in EUs. Can be fired as many times as desired, so long as EU cost to charge is paid.
Shields (screens) are expensive, requiring about 75% of total PPB, or 38% of total possible hits. for the day to raise at any point (though no further cost is incurred that day). Full screens absorb 1d6x15% of damage. Half-screens cost half, and absorb 1d6x10%.

Retreat at warp
Can evade (retreat at warp). Each ship roll 1d6. If evader’s roll is higher than pursuer’s, evade is successful. Navigator adds +2. Only supposed to evade after incurring half PPB in damage below 0 (only 25% of total possible hits remaining), unless part of some special plan, otherwise risk demotion.

Experience Points
Gaining levels means more hit points, increased skills, and rank promotion, with entitlement to bigger ship for militaries only.
Humans get +10% XP bonus, unless Psionically active.
Encounter XP split between party members
NPC crew members only receive a half share of XP
Bonuses for all: +25-100 for good ideas, or imaginative use of powers and equipment

XP Bonuses for Each Class
Command, no subclass: +10% for defeating opponents or otherwise defusing combat situations
Comannd, leadership: +100-500 for completing a mission, -50-100 per person of excess casualties
Command, security: +10% for defeating opponents or otherwise defusing combat situations
Command, fire control: +50-200 per ship defeated in combat
Science, sentient life contact: +50 per new race encountered, and up to +200 for each new race establishing extended friendly contact
Science, biology: +50 per new animal or other organism contacted or discovered, and up to +200 for each establishing extended friendly contact
Science, medical: +200-500 for each new outbreak of disease characterized and controlled, or for solving other complex medical issues
Operations, communication: +50-200 for successful “blind” Transporter beaming
Operations, navigation: +50-200 for each space journey completed within time limit set by SM, +50-100 bonus for each day under the time limit
Operations, engineering: +50 per point of ship PPB repaired, +50-200 for reverse engineering new alien technology
Enlisted: +50-200 for placing self in mortal danger for benefit of crew

Note: All XP bonuses are negated if the relevant action goes against the greater interests of the ship or crew.

Rules Mod: Main Character’s Privileges
1. Luck Reroll: 1 per session per PC
2. Call Redshirt! – Once per session any one player may call redshirt! when an attack or dangerous effect seems immanent. The attack or effect then automatically and mysteriously redirects to a minor NPC member of the ship’s crew (the “redshirt”), which cannot be a non-crew member or a major NPC such as a villain or other character around which the plot revolves. Calling redshirt! is possible only if such an NPC is present. Any player may call redshirt! Regardless of their character’s location or status, and this may only be called once in total per session. It must be called before the SM announces the damage or effect.
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Rules Mod: Criticals and Fumbles
Natural 20 is a fumble, natural 1 a critical

basic rules summary

Star Trek Odyssey BrandonDrowningInDice