The Dark Templar lynched on Day 1, the Ghost on Day 2, everyone uses their Stimpacks to protect themselves on Night 1 except Isaac so that everybody's drained on Night 2...

Role Messages
Beetnemesis

You are the Station's Medic, a Terran nicknamed "Sync". It is your job to ensure the continued operation of this Station and its Terran crew, and if at all possible, to stay alive as well. You win with the Dominion when the alien threat has been wiped out.

You have the following abilities:

Blind: Using your A-13 Grenade Launcher to fire specially modified illumination rounds, you can cripple the optical senses of your victim, effectively blinding them and removing them as a threat, at least temporarily. The target cannot employ any Night Action this Night. This counts as a Night Action.
Heal: You can target any other member of the crew and repair most injuries. This can save the life of a dying crewmember, or restore damage caused by the use of Stimpacks. This counts as a Night Action.

Artsapat, Bergioyn, Isaac, Ranagrande

You are a Terran Marine, going by the name "[Fantasy/Boxer/Casy/Mind]]". It's your job to ensure the continued operation of Daedalus Station, to root out the Zerg infestation, and if at all possible, stay alive.

To this end you are equipped with a CMC-300 Powered Combat Suit and fully loaded C-14 Impaler gauss rifle. With your other similarly equipped Marine comrades at your sight, this should be more than enough to deal with the Infested, just as soon as you've figured out who that is. You win with the Dominion when the alien infestation has been eradicated.

You also have the following ability:

Stimpack: Injections of this potent drug mixture will greatly heighten your perception and reflexes for a significant period of time, allowing you to repel any attacks for the duration of the Night. This counts as your Night Action, and you must decide whether to protect yourself or the Medic. Side effects, including insomnia, weight loss, tremors, grand mal seizures, mania/hypomania, paranoiac hallucinations, severe internal hemorrhaging and cerebral deterioration have all been declared nominal and well within the Dominion's acceptable safety margins. Still it would probably be best to wait until you have received the attention of the Medic before using this ability again.

Stephen

You are Dominion Ghost Agent #27 331, currently operating undercover as a Marine code named "Flash".

Your objective is to confirm the existence of a Zerg infestation, and if possible to eradicate it before it becomes necessary to sacrifice the Station. The lives of the crew are considered expendable, though you know that it would be dangerous to attack them directly. Ideally, as Dominion assets you would prefer that they remain alive, but you win with the Dominion when the alien infestation has been wiped out, regardless of how many Terrans survive.

You have the following abilities:

Cloak: You vanish from most senses thanks to your telepathic suggestions and the camouflage abilities of your hostile environment suit. You cannot be targeted by Night Actions for the duration of the Night. This counts as your Night Action.
Snipe: You can attempt to exterminate the target with a well placed shot. This counts as your Night Action.
Telepathy: You may read the thoughts of other living creatures. This should easily allow you to discover who the Infested are, though for the sake of subtlety, you judge that it is best to do this when they are alone, rather than risk drawing their attention when they could alert others. You can determine the allegiance of any other crew member. This counts as your Night Action.

Yunalesca

You are Prelate Nalra of the Lenassa Tribe of the Nerazim, a Protoss Dark Templar. However, using your considerable psionic abilities you have crafted an hallucination in the minds of the Station's Terrans of one of their own, nicknamed "Nada".

This Hallucination is a Terran Marine, capable of using their dangerously toxic "Stim" drugs to heighten his reflexes and repel any attack. However, once the Stimpacks wear off, a medic is needed to heal off the damage the toxins have done to the human body, before this ability can be used again.

Unknown to these Terrans, you have been altering their station in order to turn it into a weapon that will purify the world below of its Zerg infestation. This new development threatens your mission. You cannot allow yourself to be discovered, nor can you allow the station to be destroyed by the Terrans. It is crucial that the Zerg infestation be rooted out immediately. How you wish to accomplish this may determine the success of your mission:

You may choose not to reveal yourself, and act through manipulation alone to help the Terrans discover and eradicate the Zerg threat. So long as your true presence is not discovered, you win with the Dominion when the alien threat has been exterminated.

If you choose to intervene directly, or get otherwise revealed, then you will need to kill every member of the crew to ensure that your plans are safe. If this happens, then you win alone when all other members of the crew are dead.

You have the following abilities:

Assassinate: You may attempt to kill another member of the crew. This counts as your Night Action. Also, whether you succeed or not, this action reveals your existence to the crew.
Cloak: You hide yourself from most senses by the powers of the Void. You cannot be targeted by any Night Action for the duration of the Night. This counts as your Night Action.
Shield: You are protected by a Protoss Plasma Shield that can sustain severe damage before your life is ever put at risk. The Shield can protect you from one Night Kill, however, doing so will also reveal your existence to the crew. The Shield can be replenished, but doing so requires a moment of respite, which counts as your Night Action.
Telepathy: You may read the thoughts of other living creatures. This should easily allow you to discover who the Infested are, though for the sake of subtlety, you judge that it is best to do this when they are alone, rather than risk drawing their attention when they could alert others. You can determine the allegiance of any other crew member. This counts as your Night Action.


Other details that weren't revealed immediately:

If the Ghost used his telepathy ability on the Dark Templar, his presence would be revealed, and his objectives would change accordingly.

The Zerg could only use their Infest ability three times over the course of the game, regardless of success or failure. They would not gain a standard mafia Night Kill afterwards, and would be forced to rely on lynches to carry them the rest of the way to a tied situation (in a tie, all Infested Terrans could detonate, and ensure their victory that way, since they didn't have to survive to win.)

The night action order would always go in the way most unfavourable to the Zerg. For example, if an Infested Terran attempted to Infest the Ghost, while the Ghost was trying to Snipe the Infested Terran, the Snipe would go through first and the Infest would fail. Likewise, Stephen's Telepathy activated after Isaac was Infested, rather than before.

Neither the Ghost nor the Dark Templar could be Infested. If targeted for an Infest, they would die (assuming they were undefended) rather than join the Swarm.

Infested Terran kept their previous abilities, though this was only relevant for the Medic, since Stimpacks are redundant with Burrow.

Infested Terrans could communicate among themselves at any time, Day and Night.


Design concept

My idea for this game was to provide more choices for players. All the roled players (Ghost, Medic, Infested Terran, Dark Templar) had the choice of multiple Night Actions with which to pass the Night, and even standard Marines had an ability which allowed them a choice of two targets, and being a renewable one-shot, also gave them the choice of when to use it.
Likewise, the Dark Templar had two possible victory objectives, and which Night Actions she would employ depended on which method she would choose.

This didn't really play out, unfortunately.