Since D&D dropped the declaration phase in favor of cyclic initiative, it has let one round blur into the next without any phases that trigger between rounds.

Still, each round represents a short span of time that gives every combatant a chance to act. The end of a round and start of another makes a natural break to add phases or to switch gameplay. D&D doesn’t do any of these things, but other tabletop roleplaying games do, and RPGs have a long tradition of borrowing the best ideas from each other.

Retreat phase

Side initiative makes running away from a fight easier. In games like original D&D with side initiative, DMs could add deadly foes to their dungeons without fearing that players would get locked in a fight they couldn’t win. The party could run and likely escape. Defeated monsters could also run and possibly escape. In modern D&D, when monsters flee, the session typically stalls on a prolonged chase where the party still kills every foe.

Even without side initiative, a modern game could capture the same benefits by adding a retreat rule that switches the game’s usual turn order to side initiative. Retreat would work like this: At the end of a round, either side can declare a retreat and act together before the other side gets their actions. This enables the same sort of coordinated retreat that side initiative allowed. A full implementation of this idea might need a rule to prevent players from declaring a retreat and instead coordinating an attack.

Dialog phase

In movies, comic books, and tales by the fire, fight scenes often pause to the villain can explain their plan, offer to rule the empire side-by-side, or to just gloat. Meanwhile, heroes explain the mistakes that will lead to the villain’s fall. Roleplaying games need a dialog phase between rounds that gives characters a way to pause the action for roleplaying talk without anyone wondering why someone would waste six seconds talking while everyone else takes swings.

Making conditions land simultaneously

In D&D and games like it, effects and conditions end at different times, often at the end of another creature’s turn. Meanwhile, I struggle to keep track of what ends when. Judging from my years of playing, I’m not alone.

Could a roleplaying game reduce the burden of tracking when conditions expire by simply grouping the ends and save-to-ends at the end of each round? Such a rule would help everyone track when a particular effect expires.

However, such a process would create a problem: If a creature imposes a condition, then its actual duration depends on how early in the round the creature acts. So, if a creature acts last and the conditions they impose expire at the end of a round, then those effects expire immediately.

If the conditions triggered during a round all take effect at the same time, then this duration problem disappears. To explain how that might work, remember that all the action in a round happens during the same six-second span—effectively simultaneously. Back in 1979, AD&D counted six seconds as simultaneous. If traded attacks came in the same segment, they hit at once, and the attackers took damage together, potentially killing both at once. AD&D segments spanned the same six seconds as fifth-edition rounds.

What if we count all the conditions triggered during a round as starting simultaneously at the beginning of the next round. Who can say when something like poison takes effect anyway? Then every effect spans the same amount of time and neatly expires or triggers a save at the end of a round. The memory demands become simpler.

More games than AD&D allowed this sort of simultaneous effect. Burning Wheel resolves every combatant’s action before applying all the results at once. Possible results include wounded, killed, unbalanced, or knocked prone. For a game like D&D, I would impose damage the moment it lands, to reduce bookkeeping. Winning initiative still gives an edge.

This feels like a big change in play, and one that not everyone can embrace. But perhaps it would play well. D&D’s designers once suspected that innovations like cyclic initiative and advantage/disadvantage might prove too big for the game, but players embraced both changes.

Related:
Turns and Turn Order Are the Worst, so Why Do Roleplaying Games Make Us Spend So Much Time Deliberating Them?
Monsters That Run or Surrender Raise so Many Problems. How to Cope