Time mages: practitioners of a meta-school of magic of such potential for havoc that its very existence might be one of the most fiercely-guarded secrets even from some of the most learned grandmasters of magic.  Chronomancy - the power of Time itself.  Chronomancers are most typically taught this secret power by other Chronomancers, often who have been watching the candidate in secret, at multiple points in their life, and frequently from another time period than the candidate; most typical, but still extremely rare.  Even more unlikely, sometimes a Chronomancer learns this secret art by stumbling upon some text or scroll that contains knowledge of the demiplane of time, or advanced magical theory on manipulating temporal flow while also containing the paradoxical repercussions of such meddling.  Most rare of all, though it happens, a studying wizard might come to hypothesize - correctly - about the nature of time all on their own.

Depending on the setting, Chronomancy may be a profoundly secret art, or it may be a commonplace field of study.  Given the delicate nature of their art, Chronomancers might strongly tend to guard the secret of their power and their study above all else.  If it is a secret, then should this secret be let slip too publicly, or too frequently, the offending Chronomancer may find that they have a host of other Chronomancers to contend with; or worse: the native creatures of the demiplane of time.  An adventuring Chronomancer may choose to divulge their own nature to close, trusted companions, or even mentor and train a spellcasting companion in the ways of Chronomancy, but in realities where Chronomancy is unspoken of (DM discretion), the Chronomancer should avoid selling, trading, or carelessly discarding Chronomantic spells or literature.  In settings where Chronomancy is secret, Chronomancers often masquerade as Transmuters, Diviners, or a "peculiar student of magics that fall somewhere in between the two".

A Chronomancer may be an eager historian, travelling back and forward through time to record events of history with unmatched accuracy; or may be an opportunist, jumping to points in time when things are (or will be) known to have gone mysteriously missing... only to return home to fame or profit; or could be an idealist who leaps through time, righting wrongs, restoring timelines to "what they ought to be", or attempting to alter events to suit their own personal ideal history of a family, city, or realm - though often things work out in a way unexpected by the meddler.

In all cases, Chronomancers understand the dangers of recklessly meddling with the histories of reality, at best trying to repair or prevent damage to the fabric of reality whenever they see problems, and at least attempting to avoid getting caught up in any untempered temporal paradoxes personally.  Even those who manipulate time for selfish gain or personal ideology understand that there are some laws of nature that should not be carelessly ignored.

DMs Note: Chronomancy and time travel are very advanced and complex concepts to include in a single-author story, let alone a multi-author role playing campaign.  Be sure you are familiar with this subclass and any spells published here or created by you or your players before you consider allowing this subclass to be used by a player.  Regardless of whether it is a player or an NPC who is granted the Chronomancer subclass, it is also recommended that you decide beforehand upon some in-game nature of time for resolving changes to the story due to time travel (examples: if you go back and change something: did you really just branch into an alternate reality? ; or did you actually change things in the future but are still able to remember the original past events? ; or did you actually change nothing at all and this was how things were ALWAYS meant to happen? ; or do changes made to the past always result in a series of unexpected events that end up producing the same outcome no matter how hard anyone tries to change it (the time traveller's fiance always dies on Tuesday by some means no matter what is changed) ? ; etc).  Also be sure to talk with your player(s) beforehand and make sure this material is used with the goal of everyone having fun and making a more interested and exotic story together, rather than one player gaining more power than the other players, or being destructively disruptive to the campaign or setting.

Exclusive Studies

When this subclass is selected at 2nd level, the Chronomancer permanently gains access to a new meta-school of magic: Chronomancy.  While this isn't actually a school of magic, but rather a new way of thinking about magical properties of many of the existing schools of magic, only a Chronomancer may learn and cast these spells.  Anyone may attempt to read your spellbook, but only a Chronomancer would ever be able to make sense of any spells of the Chronomancy meta-school recorded therein. To all other magically fluent readers, these spells simply appear nonsensical.  When this subclass is selected, the Chronomancer immediately trades at least two of their currently known level 1 Wizard spells for an equal number of level 1 Chonomancy spells, and trade at least one of their known Wizard Cantrips for an equal number of Chronomancy Cantrip.  It is strongly recommended that at least one of the Chronomancer Cantrips taken is Detect Temporal Anomaly.  Finally, the Chronomancer gains proficiency in the history skill and can apply this skill to both past and future events and all Chronomancers study how the past repeats itself. And at 6th level they gain expertise in the history skill as they have honed their knowledge of the past, present and future.

Alternate Reality

Beginning when this subclass is selected at 2nd level, the Chronomancer learns how to create small variations in the probabilities of reality. Each variation lasts only a moment, but creates alternate results for one recently-past event. When altered in this way, any one event attempted by a target the Chronomancer could see during the previous round is recalculated, essentially allowing (or forcing) that character or creature to make a new die (or dice) roll. Only events that begin and end in a single round can be affected in this way. Only one roll-event can be rerolled. If the target is a willing recipient, the Chronomancer can choose which roll (the original or the new roll) affects them. If the target is unwilling, they must reroll the action and accept the new result, whatever its outcome.

Typical uses of this ability include: allowing a fighter to reroll an attack; forcing an opponent to reroll a successful saving throw; or allowing a wizard to reroll the damage caused by a weak fireball.

In order to use this ability, the Chronomancer character throws a small, unmarked die. Each alternation can be made only once per turn, and only two such alternations can be made by the Chronomancer until a long rest is taken.

Time Management

Beginning at 6th level, casting spells with concentration has become more manageable to you that you can have two concentration spells active at once. However there are a few restrictions to this, first you must spend one round preparing for this and use your Action to time it all out. On the next round you will cast both spells within one action, however one of the concentration spells must only target one creature. If your concentration is broken during the preparation of these spells, you only lose one spell slot. You also have the ability to keep track of time accurately and you never forget time sensitive events.

Out of Time

At 10th level as part of your movement action or as a reaction to being attacked you briefly stop the flow of time for everyone but yourself. No time passes for other creatures, while you take the rest of your turn, during which you can use actions and move as normal. During this time creatures not native to the demi plane of time are treated as if they were paralyzed. If you used this feature as a reaction during combat your initiative order has moved to the turn right before attackers. If you moved out of the location you were being attacked, the attacker's action is wasted, but it may finish the rest of it's turn.

For example, if the attacker has multi attack, then only one attack may be foiled, and so if it is able to move to your new location it may still be able to use the rest of its attacks against you.

Once you use this feature, you can't use it again until you finish a short or long rest.

At 14th level you can use this ability twice per short or long rest, but not on the same turn.

 

Greater Improbabilities

Starting at 14th level, Alternate Reality can now be used up to three times per long rest.