How to Play This Game is KILLER: Alien On Board Step by Step

Quick answer

To play This Game is KILLER: Alien On Board, deal hidden role cards, complete the setup as described in the rulebook, then run rounds of discussion and voting to identify the alien among you. The crew wins by ejecting the alien; the alien wins by surviving or eliminating enough crew. Always confirm your edition's exact win conditions in the included rules.

This Game is KILLER: Alien On Board is a social deduction game where one or more players are secretly the alien while everyone else tries to figure out who. If you have never played a hidden traitor game before, the first round can feel chaotic. This guide walks you through setup, the round loop, and the mistakes that sink new groups.

The steps below assume you have the physical game and its rulebook in front of you. Because publisher rules can vary by edition, treat this as a practical framework and check the rulebook for exact card counts and win conditions. Once you understand the flow, the game runs on conversation, bluffing, and a few key decisions.

What you need before you start

This Game is KILLER: Alien On Board is designed for a group, so the first requirement is enough players to fill the hidden roles. Check the box or rulebook for the supported player count. You will also need a table where everyone can see each other, because social deduction depends on reading faces and body language. Clear a space in the middle for any shared tokens or cards.

Set aside 45 to 60 minutes for your first game. New groups spend extra time reading role cards and arguing about who is suspicious. Once everyone knows the flow, rounds move faster. Have the rulebook open on the table for the first two games so you can settle disputes without guessing.

• Do not skip the rulebook even if you have played similar hidden traitor games; this game's roles and win conditions are specific.
• Put phones away. Side conversations and screen glances break the social deduction tension.

Step 1: Set up the hidden roles

Shuffle the role cards and deal one to each player face down. Players look at their own card in secret and keep it hidden. In most social deduction games, the crew members know they are crew, and the alien knows they are the alien. Some editions include special roles with extra powers, so read your card carefully before play begins.

A common mistake is dealing roles before explaining what each role does. Walk through the possible roles first, then deal. That way nobody has to ask a revealing question mid-game. If your group is new, consider playing one practice round with all roles revealed so everyone sees how the pieces fit together.

• Checkpoint: every player should be able to say 'I understand my role' without naming it out loud.
• If you accidentally see another player's card, tell the group and reshuffle that card rather than playing with known information.

Step 2: Run the first round

The first round usually starts with a short discussion phase. Each player says something about their role or suspicions without revealing their card. The alien's job is to blend in, agree with reasonable points, and avoid being the first name thrown out. Crew members should ask specific questions rather than vague accusations.

After discussion, the group moves to a vote or action phase as described in the rulebook. This is where the hidden traitor game gets tense: someone gets ejected, and everyone immediately second-guesses the result. Keep the pace moving. Long silences favor the alien because they give it time to build a cover story.

• Common mistake: voting too fast in round one. Give everyone one full pass to speak before any vote.
• If your edition uses a timer, set it and stick to it. Timers prevent endless arguments.

Step 3: Use information, not noise

In social deduction games, the crew's advantage is information. Pay attention to who defends whom, who changes their story, and who avoids answering direct questions. The alien's advantage is confusion, so a player who creates chaos without adding facts is worth watching. Take mental notes rather than writing them down, since visible notes can reveal your suspicions.

When you speak, make one clear point and let others respond. Players who talk constantly often get ejected because they look like they are hiding something. Players who say nothing also get ejected because they look suspicious. The sweet spot is steady, specific participation.

• Beginner tip: repeat back what someone said before you challenge it. It keeps the discussion calm and exposes contradictions.
• Do not accuse someone just because they accused you. Revenge votes usually help the alien.

Step 4: Handle the alien's win condition

The alien wins by surviving until the end or by meeting whatever condition your edition lists, such as eliminating enough crew. Because exact win conditions vary, check the rulebook before you start. If the alien is close to winning, the crew needs to take a risk and vote, even without perfect information.

A common mistake is treating the alien as a passive role. The alien should actively steer suspicion toward a crew member, but not so aggressively that it becomes obvious. The best alien play looks like a concerned crew member who is simply wrong about who to trust.

• Checkpoint: at the end of each round, ask 'what did we actually learn?' If the answer is nothing, the alien is winning the information war.
• If your group plays multiple games, rotate who deals the roles so the same person is not always the alien.

Step 5: End the game and debrief

The game ends when one side meets its win condition. Reveal all role cards and confirm the result. Then spend two minutes talking about what gave the alien away or what made the crew miss the signs. This debrief is where new players learn the most, because they hear how other people read the same behavior differently.

If you enjoyed the hidden traitor tension, try a cooperative deduction game like Adventure Party: The Role-Playing Party Game, where players work together instead of accusing each other. It is a good palate cleanser after a tense round of suspicion.

• Do not skip the reveal. Seeing the roles confirms the game was fair and teaches everyone for next time.
• If a rule dispute happens, check the rulebook before the next game, not during the reveal.

Your first game, step by step

1. Confirm player count and roles: Check the rulebook for the supported player count and which roles are in play. Deal role cards face down only after everyone understands what each role does. Checkpoint: every player can describe their role's goal without naming it.
2. Run the first discussion round slowly: Give each player one uninterrupted turn to speak. Ask specific questions instead of vague accusations, and do not vote until everyone has spoken once. Common mistake: rushing the first vote and ejecting a crew member by accident.
3. Vote and resolve the round: Follow your edition's voting or action procedure exactly. Reveal the ejected player's role if the rules say to, then move to the next round. Checkpoint: the group agrees on what was learned before starting the next round.
4. Watch for alien behavior, not volume: Track who defends whom, who changes stories, and who adds no facts. The alien wins by creating confusion, so reward clear information with your trust. Beginner tip: steady, specific participation looks more trustworthy than silence or constant talking.
5. End the game and debrief: Reveal all roles when a win condition is met. Spend two minutes discussing the tells and mistakes so the next game is sharper for everyone. Next step: rotate the alien role and play again while the lessons are fresh.

Games that pair well with hidden traitor nights

• Adventure Party: The Role-Playing Party Game: A cooperative, party-weight, guessing game that delivers a robust role-playing experience. You and your friends are classic fantasy characters facing up to 3 unique adventure scenarios, rolling a 20-sided die behind a player screen so no one can see the result. If your group likes hidden information but wants cooperation instead of accusation, this is a natural next step. The secret die roll keeps the same tension without turning friends against each other.
• The SPILL: a dynamic co-op game of saving our oceans from a disaster: A fully co-op game featuring a 4-way dice tower pouring oil into the ocean. Your response team must work together to avert an ecological disaster. Another fully cooperative option for groups that want shared problem-solving. The physical dice tower adds a dramatic centerpiece that keeps everyone engaged between turns.

This Game is KILLER: Alien On Board rewards groups who talk, listen, and commit to a vote. Learn the setup, keep the first round slow, and debrief after every game. If you want the same hidden-information thrill without the accusations, try a cooperative game like Adventure Party: The Role-Playing Party Game or The SPILL.