Convergent Future vs. Portent

[Nagog]

In a direct lineup, which effect would take? And how does Advantage/Disadvantage play into their use?

In my mind, Portent is trumped by Convergent Future, simply due to the wording: Portent says it replaces the roll, Convergent Future says to ignore the roll entirely. For the same reason, I'd say that Portent could replace one roll when rolling at advantage/disadvantage (but not both, as once per turn), but doesn't necessarily determine the overall outcome.

What are your thoughts/how would you rule on these?

[JNAProductions]

It would help to explain what the features do, or at least where they can be found.

[MaxWilson]

It would help to explain what the features do, or at least where they can be found.

Convergent Futures is a 14th level wizard subclass feature (Chronurgist, Explorer's Guide to Wildemount). Whereas Portent (Diviner 2 feature, PHB) lets you choose not to roll, preempting it with a predetermined roll of your own, twice or eventually three times per day on any creature you see, Convergent Futures is used _after_ an attack roll or saving throw or ability check (for creatures you can see within 60') to override the results of the roll and essentially ensure auto - success or auto-failure as you choose, at the cost of your reaction and a level of exhaustion which can only be healed by long resting.

"Essentially" because what you actually do is set the die roll to the number right at the minimum number for success or the maximum number for failure (depending whether you wanted success or failure), so things like Bardic Inspiration or Cutting Words can still change the outcome.

Portent can get wasted if success was likely already before you rolled; Convergent Futures never gets wasted unless you guess wrong about whether the roll was going to fail.

Note that Chronurgists also get a similar ability at level 2 which forces a reroll on a reaction instead of an autoresult. Its 6th and 10th level abilities are excellent too. Overall Chronurgist is stronger than Diviner, IMO enough to be poor design.

[JNAProductions]

Okay.

Convergent Futures seems like it'd override Portent. It's both a higher level feature, and can affect AFTER the roll, while Portent just replaces the roll with a predetermined result.

[Dork_Forge]

Convergent Future would win out because of the order of operations, Portent needs to be used before the roll, if the Portent die makes the roll suceed or fail then Convergent Future can then be used to override it. The Chronurgists 2nd level feature would also win out over Portent for the same reasons.

[kazaryu]

In a direct lineup, which effect would take? And how does Advantage/Disadvantage play into their use?

In my mind, Portent is trumped by Convergent Future, simply due to the wording: Portent says it replaces the roll, Convergent Future says to ignore the roll entirely. For the same reason, I'd say that Portent could replace one roll when rolling at advantage/disadvantage (but not both, as once per turn), but doesn't necessarily determine the overall outcome.

What are your thoughts/how would you rule on these?

considering convergent future takes place after the roll, it would overrule portent.

as far as adv/disadvantage. i always consider them to both be the same roll unless an effect specifically calls it out. biggest reason to do this with portent is that, if you don't, then the 2 biggest uses of portent become nullified.

forcing a failure on an enemy when they should have advantage..its strong, but thats why portents are so limited. meanwhile, if you can only replace one of the dice, then all your doing is removing their advantage. because your basically picking 'this will be the low roll'. meaning the only roll that actually matters is the other dice.
the opposite is true, ensuring a success on an ally's disadvantage roll. the portent becomes all but worthless. keep in mind this is basically the only mechanical reason to play diviner. their other features typically aren't that useful.

so all you're doing is putting further limitations on an already super limited resource. and imo its a little unnecesary.