There are four game modes in OSR+, each of which has a variety of actions PCs can take unique to each mode. When you design a scene in the adventure, you must also decide which game mode the scene runs under.
For example, if you had a scene that involves the PCs fighting a monster in the woods and you planned to use a battle map for the combat, an encounter is probably the best game mode to use, because the actions available in that mode break things down moment-to-moment.
If your scene has the PCs investigating haunted house, you'd probably choose the exploration game mode.
In this section, we'll explore what mechanics you can bring to bear when you resolve action in each game mode.
Types of Game Modes
When in exploration mode, your role becomes reactive. You narrate what the players can interact with in the scene, and then they interact with those things at their own pace. Time passes in the scene in real time (the speed of player interactions) unless you decide to switch gears to encounter mode or enter abstract time via the dungeon crawl mechanic, for example.
The most common downtime action is the parley, which is a social interaction between players and/or NPCs, but you can also run downtimes that take place in abstract time and may invoke other actions (journeying and montaging, for example). In all cases, you'll need to be an active force moving the spotlight. Recovery is the simplest, since it involves players resetting their abilities.
In OSR+, most encounters are handled in much the same way as other traditional simulationist RPGs: by turn-by-turn initiative, where a discrete set of actions are possible within each turn. Encounter mode doesn't have to involve only combat, however—any time there is a need to slow down and figure out turn order, encounter mode is what you'd want to switch to.
The overworld considers what's happening in the fiction outside the point of view of the players. Like encounters, overworld play includes a discrete set of actions that govern how you create global story tags. Overworld play typically happens in abstract time.