The Chronologist (Class in 30 minutes, PEACH)

[Morphic tide]

Seven Steps Ahead (Su)

At 20th level, chronologist's actions are always in flux, and they have made every concievable preparation for the situation they're in. A chronologist may devote some amount of time to using this class feature to do something, and then later declare that they were doing a specific action.

For example, the chronologist devotes half an hour to using the class feature in a dungeon corridor full of broken miscellanea. When enemies approach for the north, the chronologist declares that they were using that half hour to build a barricade out of the miscellanea: a barricade suddenly forms in the area out of the objects. The chronologist can't declare they were doing something that would disallow someone from occupying a position they're currently in (such as declaring they built a barricade somewhere that creatures are standing) but they can make someone fall (by declaring that they dismantled a barricade that someone's on) or retroactively cause impossible situations (like declaring they built a barricade in a location that the enemy just ran through).

Similarly, the chronologist can declare they set a trap in a location such that it will trigger immediately or that they took an object with them when they had a chance.

However, this requires such an immense surge of effort that declaring what their actions were requires their entire round of actions, no matter how many they're normally entitled to. Further, if they don't declare what actions they were taking during that time within 24 hours, the benefit is lost.

This class feature replaces Turn Back Time.

There's a fundamentally broken interaction with crafting system access, here. Namely, you can spend the time to craft some unit of wealth and retroactively declare yourself to have made any item you could have made in that time within the next day, getting exactly what you need. Basically, you get the perfect item for the task, within the wealth limit offered. Fortunately, the no multiclassing rule cuts off magic item crafting access, so you aren't making the perfect 10k GP item with 8 hours prep time at level 21. But hypermundane crafting has the problem with sufficiently inflated scores to craft useful items in one day.

Edit: Absolutely horrific thing that could be done in Gestalt is retroactively declaring your prepared spells as a Wizard as needed, becoming extremely close to a spontaneous caster. This could also be done in high-epic, as there's extremely little point to keep picking spellcasting classes past level 25 or so due to the progression being maxed out.