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Bring fallen co-op players back at a spot that keeps the team together
If the dead player respawns at the start, they spend minutes walking back; if they respawn at the front, they skip the part the team still fights through, or land among enemies. Picking the right checkpoint depends on where the living players are. Here is the rule and the case when nobody is left.
Let teammates bring a downed player back up, alone or together
A downed player waits to be helped up, and a countdown decides how long. The tricky part is what happens when a helper is hit and steps away, or when three helpers arrive at once. Done carelessly the work is lost on every interruption, or more helpers make it absurdly fast. Here is a timer that feels fair.
Adjust enemy toughness when a player joins or leaves mid-fight
A boss built for one player is a joke for four, and a boss built for four is impossible for one. Scaling by player count is the standard answer, until someone joins mid-fight and the boss heals to full or someone leaves and the boss suddenly dies. Here is how to rescale without either surprise.
Decide when a team with shared lives has really lost
With a pool of lives shared by the whole team, the end of the game is not simply "lives are zero". Everyone can lie on the ground at the same moment while lives remain, or the last life can go while a friend is still standing. Here is the rule for when the game is over and who comes back.
Choose where a returning player appears so they are safe but near the team
A player who comes back into the fight right in front of an enemy dies again at once, and one who appears on the far side of the map is useless. A good spot is away from danger, close to friends, and not the one that was just used. Here is a way to choose, including what to do when every spot is dangerous.
Share loot in a co-op game so nobody always walks away empty
When a team finds treasure, pure chance lets one player collect everything while another gets nothing for an hour, and that player quietly stops playing. Letting everyone grab is no better. Here is a fair handout that remembers what each person already received and still respects who actually wants the item.
Split players into two teams that are really even
Picking the strongest player for one side and the next for the other looks fair and often is not, because the last players decide the sum. For a lobby of ten or fewer, the best split can simply be found. Here is how to find it quickly and what to do when the player count is odd.
Keep a turn-based team game moving when someone is gone or asleep
In a game where players act one after another, a single disconnected or distracted player can freeze everyone for good. Skipping them sounds easy, but the round counter, the returning player and the case of only one person left each need a clear rule. Here is the order that never gets stuck.
Settle who gets the last item when two players buy at the same moment
Two players press buy on the last potion in the same instant. Without a clear rule both get charged, both get it, or only one gets it but nobody can say who or why. Here is how the server decides fairly by arrival order, why the player's own clock must not count, and how the loser keeps their money.
Send a whole army to one spot without all units piling up on one square
If you order twenty soldiers to one point, they walk to the same square, push each other and shake in place. Here is how to hand every unit its own place around the target, skipping walls and the map edge, so the group arrives calmly and the nearest ones take the best spots.
Tell a click from a drag so selecting units feels right at any zoom level
Selecting units with a box sounds simple, until a shaky click starts a tiny box that selects nothing, a box drawn backwards selects nothing at all, or a zoomed-in map selects the wrong units. Here is the logic that behaves the same for every hand and every zoom.
Stop enemy units from switching targets back and forth every turn
When two targets look almost equally good, an enemy that picks the best one afresh every turn runs left, then right, then left again and never attacks anything. Here is a small rule that keeps a choice until something clearly better appears, and picks the same one every time on a tie.