Most games of Messina end after ten Rounds, or after a previously agreed even number of Rounds (six or eight rounds for a shorter game). Premature game ends are possible if one faction is virtually eliminated: if any faction loses both of its Home Spaces to invading land forces on a Round, that Round is the final Round. If game-ending conditions are reached during a Military Bonus Action, the players yet to choose an Action on the final Round still get to complete the Round, and the resulting Military Operations Phase still takes place. The game is not prolonged if the game-ending condition is later reversed. The final Round ends with a Final Consumption Phase even if it is an odd-numbered round.
To lose a space:
- the faction must have no surviving Units on the space (including Worker Units)
- the space must be occupied by hostile Units
- there must be no friendly Units from other factions on the space.
Holding a Card for a space does not by itself constitute having a friendly Unit on the space, and does not prevent a space from being lost, but a face-up Card with a friendly Unit on it does constitute having a presence in that space. Having infrastructure on a space does not by itself constitute a presence on that space – if the space is held by hostile Units, unopposed by friendly Units, the hostile faction now owns the infrastructure.
Contenders for victory consist of pairs of viable allied factions. Viability is defined as both members of the pair still holding at least one of their Home Spaces (and, for the AI, still holding the Starship and, for Cryos, still holding the Moon), and the pair has achieved a positive score following the Final Consumption Phase. An alliance is arranged by mutual consent, but it is not possible if the two factions have battled in the final two planned Rounds, or if either player has ever used the Skill Card “Dirty Bomb” against the other. Each faction may only nominate a single alliance partner. If the AI has surrendered the Kill-Switch Card to another faction, the AI and that faction must form an alliance, and the AI cannot claim a solo victory.
Allied pairs then enter a Final Consumption Phase, in which they:
- Pool all resources, including population
- Occupy Utilities under normal restrictions
- Operate all occupied utilities up to twice each, without regard as to who owns which resource.
- Count how many Population Tokens they can feed and water twice (equivalent to counting completed 3-token sets of 1P+1W+1F). This is the Well-Fed Population.
- Count how many Population Tokens cannot be fed and watered twice. This is the Poorly-Fed Population.
- The final score is the Well-Fed minus the Poorly Fed Populations: WF – PF.
The only Skill Card benefit that can be applied during operation of Utilities is Utility Mechs. [This will be written on the Card]. No Skill card benefits can be used to provide Food or Water discounts.
The pair with the highest positive score (>0) wins. Both members of the pair share the victory equally, regardless of their contributions to the population total. If no viable allied pairs exist and the AI faction is still holding the Kill-Switch Card, the AI wins. If no allied pair is viable and the AI has previously handed over the Kill-Switch Card, everyone loses.
If two different viable allied pairs achieve the same positive score, the pair with the member that is highest on the Crypto ladder wins.