RPGMemes

It really depends.

I'm thinking about 3.5 in particular, where an optimized wizard will be able to do the job of the rest of the party (assuming they're built to be fine, but not power-gaming), better than them.

There's no real in-world way to balance that. Either the DM Fiats the power-gamer weaker, the DM tells the power gamer "no", or the rest of the party power games to. Its just too unbalanced.

If we're talking 5e, that's all out the window then. If 3.5's power runs from 0-10, the strongest 5e build is like a 6, and the weakest is like a 3. Its still extra work for the DM to balance, but can be done all in-world without needing to rely on metagame fiat.

And, of course, there's lots of other systems out there, where the above can be more true or less true depending on what kind of game it is, though 3.5's power ceiling is probably higher than 95% of the systems out there.

First off, you’re relying entirely on spells you have no guarantee of ever getting. You’re a wizard. You don’t get to just choose spells willy nilly. You find those and you copy them into your book or you learn from some other means. No guarantee of those means.

What?

Wizards can choose two spells each level without having to find them.

Only dealing with the L10 scenario.

(1) You get to choose two new spells at level up, in addition to those you find elsewhere. Assuming your DM hasn't restricted sourcebooks.

(2) This is where catnap is required. It shortens a short rest to ten minutes (at the cost of an L3 slot). This allows you to create new motes before the previous ones have expired.

(3) the motes are being triggered by familiars, who can become the concentration holder. How do you get that many familiars? Well, you give your familiar motes with Find Familiar and have them crush them.

Furthermore, each familiar can then dismiss their familiar to their pocket dimension for unbreakable concentration.

Everything works, rules as written. Broken? Yes.

L15 scenario. The above are two entirely separate scenarios -- I was not assuming two chronomancers in the same party.

Let's simplify this from an action economy perspective so we aren't running into the reaction limits. Let's assuming combat lasts four rounds, and on each of the first three rounds, you cast Polymorph (killer whale), and use your Chronal Shift to force a reroll if they save, generally with the goal of burning legendary resistances. Obviously this works better with a bigger party casting save or suck, to burn them faster (you can only Chronal Shift once per round though) or you can use the L10 trick above if well prepared. Great, in the fourth round, you cast Polymorph (killer whale) again and force them to fail the save as a reaction. Take one point of exhaustion. Easy enough, right?

Well, magic jar is fun, but requires serious prep to reduce the risks. An L15 wizard should already have a lair where they can leave their body safely, and they'd need to capture their target and bring them to their lair. This is why I chose L15 for this scenario instead of L14, because you need access to the spell. Assuming your wizard has a Researcher background or something (so you can handwave the meta), you can use locate person to find a CR12 Duergar Despot who has immunity to exhaustion. They exist in Forgotten Realms at least. Your DM might rule they don't exist, and then you'll have a harder time finding a humanoid immune to exhaustion to capture to magic jar into. That whole capture scenario would be an amazing multi-session mini-arc.

So worst case scenario, the DM says such a target doesn't exist. Well, then you have to wait until L17 to pull this shit off. True Polymorph can create a humanoid that is immune to exhaustion (there are dozens of them!) to create a magic jar target. Or you can use Wish (also broken) to summon such a creature, or simply wish yourself immune to exhaustion.

I mean, if you're an L17 wizard, you're basically god anyway. But the Chronomancer can pull off godhood at L15 if they can become immune to exhaustion with magic jar.

Even at L14, with the exhaustion penalty, it's stupidly strong.

Side note: killer whale is my go to. It's huge, thus hard to carry away by minions; has a huge bag of hitpoints, hard for minions to slap once to return back to BBEG form; and has a speed of zero on land. A good BBEG will have contingencied dimension door or something, so it isn't foolproof. You can try to trap them in Mordenkainens Magnificent Mansion or something that prevents escape through teleportation, but that adds another layer.

Did I mention that wizards are broken?