Choose a rule that reads on screen
Pick a short challenge with an obvious goal and observable result: land three clean placements, finish without a miss, or beat your own previous score. Avoid a challenge whose key event happens off-screen or depends on viewers sharing the same game state. A simple scoring rule helps a watcher understand the attempt before they decide whether to play.
Write the challenge before the game
Try a format such as “play Stack three times; your best tower is your score” or “finish one run without a miss.” State the attempt limit, scoring method, and whether a restart uses a fresh attempt. If viewers suggest a modifier, have your poll decide the next version before play rather than implying chat can alter a live game session.
Run a small safety and fairness check
Play the challenge once as a new viewer. Check that the goal, control cue, and score are visible on the broadcast, then verify the same public game page is easy to find for an independent run. Decide how scores will be compared and say when participants are reporting them themselves.
A simple host-run poll can choose between two safe modifiers, while the game prompt keeps the resulting rule stable for every attempt. Prefer a mechanic or fictional mascot over a viewer's real name or private chat quote; the published version can be encountered outside the stream.
Questions about game ideas for streamers
What kind of challenge is easiest for a viewer to join late?
Use a repeatable score or completion rule with a fixed number of attempts. A viewer can understand the goal from the current stream and try the same public game afterward.
How do I keep viewer scores fair?
Use a fixed attempt count and a scoring rule players can see. If results are self-reported, say so; do not describe them as automatically verified.