Chronovoyance

When casting this ritual spell, the caster must state the time frame they are seeking to review up to the maximum based on the level of spell slot used, as well as how long they will concentrate on the spell (up to the maximum for the spell slot used). The events they view are in real-time, meaning that if a spellcaster wants to review the events of the last 24 hours, they would need to cast chronovoyance with a 6th level spellslot in order to view the entire events of that 24 hour period. If the spellcaster were able to hone down their needed viewing period to a 30 minute timespan, they could then cast the spell at 4th level and state the specific 30 minute timespan they wish to view, based on the table below. 

When targeting specific events in the past, the more information the caster is able to specify in the casting makes the accuracy of the spell all the better. When casting the spell, if the caster/player does not have full information on the exact timing of the events being viewed, they may roll an Arcana (Intelligence) or History (Intelligence) ability check as appropriate to the circumstances with a DC set by the DM (optional modifiers are provided below for ease of play). If the caster has detailed information may be as easy as a 10 or even automatic success, or if they have only vague information or rumors the DC may be 25 or higher. It depends on the situation.

While concentrating on this spell, the caster may see all the sights, sounds, and events of which they are personally capable of perceiving from their location. Higher level spell slots may present a challenge for casters who have a need for sleep, which may require constitution saving throws to stay awake, levels of fatigue, etc. The caster will not be able to see events within anti-magic fields, or where scrying would normally hide an individual. While concentrating, the caster is unaware of anything happening currently around them - to them it is like they are standing in the past. This can present a challenge if the terrain has changed recently. 

 Cast at a higher level, this spell allows you to observe farther into the past, and increases the duration of the spell as well as the events witnessed if the caster desires (they may choose a timespan viewed lower than their spell slot level, for example, a 9th level chronovoyance could target a one-round period 100 years ago if they knew enough information to target that moment in history.

The more ancient the period of time reviewed, the more fuzzy details become, imposing penalties on any attempts to perceive specific details. If the caster knows exactly when an event occurred, they may choose to only review a short period of time. For example, a level 18 wizard might cast a level 9 chronovoyance spell, specifying 8:45 AM 100 years ago on the first morning of April and only review 1 minute or even one round of time in real-time. Alternatively, for historians that have extended life-spans and no need for sleep, it is feasible that they might cast chronovoyance at 9th level, and review the last 100 years in real time. At 9th level, a spellcaster may attempt to target events beyond 100 years in the past, but each 100 years imposes a +5 to the DC of the arcana/history check to successfully view the right events. 

A failed arcana check will either cause the spell to fail, or will superimpose events from a different moment in time from the past at this location. Additionally, if a DM rules you have enough, specific information, no arcana/history check is needed.