Mirtek said:
Only if anybody else also takes their break when the characters do. Like you said: People know how the physics of magic work and will exploit it to the limit if they know that their adversaries will take the rest of the day off after 15 mins of fighting.
The party might retreat to rest, but after the have rested, the adventure is already over, because the other side did not rest.
If the other sides plans involve fighting, they will also suffer from the 15 minutes.
Furthermore, there is a limited amount of resources the NPCs have at their disposal. They can't reinforce their defenses indefinitely.
Example Scenario:
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I once mastered a scenario where an underground country has found a teleportation portal. It lead to a buried underground area, and they found it sealed and so it was mostly useless for them - until some hapless dwarven miners broke through the seal during their mining operation. The NPC army reacted quickly enough and managed to get the town under their control. Since the major army was using the teleportation gate to find elsewhere, they just created a beachhead, until they could actually launch a massive strike at the surface dwellers. I decided beforehand how many troops they had, and what reinforcements they could expect. Possible "endgame" scenarios could be (assuming the PCs wouldn't fail)
- total defeat by the PCs.
- closing the portal after the PCs deal enough damage
- arranging a peaceful solution (for the time being), allowing the use of the portal for trade. (This would require effort from the PCs to convince the NPCs to do so.)
- Taking control of the teleportation portal by the PCs and the town.
Well, the PCs are asked to contact the occupied town since they expected some travellers from there. They quickly dispatch the soldiers occupying the town, and then enter the mine.
And here, D&D attrition-based encounters is at its best. The enemy defensed their underground base well. The PCs manages to get into the upper level, and dispatch a lot of soldiers. Unfortunately, they have to retreat.
The NPCs regroup and reinforce their defenses. But there is a limit to what kind of resources they have, and so they can't create an impenetrable wall. So the next PCs attacks prevails again, but this time, they need to rest even earlier.
The NPCs use this oppertunity to send a strike force out to attack the PCs at night. The force isn't in unlimited strength (but still considerable), because the NPCs don't know what's really going on on the surface (there might be an army waiting for them), so the PCs eventually prevail again.
AFter not hearing from their force, the NPCs change their plan. They trap the upper part of the section, and retreat to a better defensible position. And again, the PCs enter, kill some foes, and retreat.
A this point, things felt already a bit ridiculous. I didn't want another attack/retreat. The NPCs couldn't really "win" anymore. So I gave them, again, some relief troups, reeinforced their defenses, and decided that this would be the last try. If it failed again, they would leave and block the teleportation portal until they had an army to defend the gate.
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My conclusion:
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But ultimately, in retrospect, the constant retreating, while sensible within the rule framework (and maybe even from a "realistic" perspective) felt unsatisfactory for me as the Gamemaster, and I got the impression that the players felt similar. The scenario would have worked just as well if it was done in one or two days, and some feeling enemies alerting their superiors over the course of the day / between encounters to get some resources. Their could have been even a time "ticking" where the PCs have to get to the teleportation gate to close it before the nasty ubermonster/NPC arrives...
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