Standard missions are usually all available. Their behavior can be modified with some configuration options, and some can even be disabled completely. The mission descriptions will contain appropriate notices.

Hosts will normally not have to do anything to support extended missions. Hosts may wish to disable extended missions, perhaps if they are upgrading a game from HOST to PHost and do not wish to unbalance a game in progress. The AllowExtendedMissions config option can be used to disable extended missions.

The only thing hosts may need to consider are other programs that also make use of the extended mission (M.I.T.) interface. If the missions used by another program overlap with those used by PHost, then the mission numbers must be changed to eliminate the overlap. For PHost, the extended mission numbers can be moved by manipulating the ExtMissionsStartAt parameter. As of this writing, there is no known add-on which could cause conflicts. We strongly advice you not to change ExtMissionsStartAt without a serious reason; this will most likely only confuse your players.

The only program known so far which also uses extended missions is FHost; it uses numbers starting with 200.