A lone Mythic PC in a non-mythic campaign, balanced or completely unfair?

[Desril]

I'm currently debating whether or not I want to seriously try getting my GM to OK letting my current PC have a mythic ascension moment in a non-mythic campaign, but I'm not 100% on the balance of adding a single mythic PC to a non-mythic campaign and would like to get more opinions before making a decision.

Character Plot related reasons are possibly going to end up leaving my PC 1 level lower than the rest of the party (it hasn't happened yet and probably won't until roughly level 8 or 9), but rather than just trying to do a side-quest to make up for lost XP, it's my character's goal to take the Test of the Starstone, and it could be more interesting to do that and get a Mythic Tier than a sub-quest to regain a lost level. So it wouldn't be 1 character with equal level in addition to mythic tiers, it'd be a character a level lower with 1 mythic tier (and in a non-mythic campaign, so Trials would be probably extremely limited. If I do talk the GM into it, I don't expect to get to, let alone beyond, Tier 3, and there's already a house rule in place that 8 hour sleep = full heal)

Has anyone here run a game where a single character had 1-2 mythic tiers and a level deficit compared to the rest of the non-mythic party (or the reverse, a single higher level non-mythic character in a mythic party)? How did it go? Was the mythic character weaker on average? Stronger? I know that, officially, 1 tier = ~1/2 class level, but theory doesn't always translate to reality in game, as proven by CR at high levels.

For those interested, the campaign and character in question is Rise of the Runelords (currently in chapter 2) and a kensai bladebound magus.

[The Bald Man]

We just finished a mythic campaign. Mythic really lives up to the name.

The power jump granted by the first mythic tier is HUGE. Bigger than any single level in any class.

The first mythic tier is so significant that you will overshadow the non-mythic PC's even considering a 1 level deficit. Especially if you choose your feat and path abilities carefully. For a class like the Magus that can take advantage of the best of both the martial and caster paths it can get crazy.

I know this isn't what you wanted to hear, but if balance is critical at your table you shouldn't do this.

[Caius]

Even low tiers I would honestly say that a single tier is equal to about a 1 level increase. You can start to do some really crazy stuff, though you are limited by mythic power for some. Assuming you are playing with others, I would not. Depending on what you took you could easily dominate a fight without expending anything. If you are playing a solo game (you have a main PC an some npcs to control while the dm runs) that'd be up to what the gm wants, but if you're playing in an actual group I feel it would be unfair to the others at the table.

[Ninja in the Rye]

I'd say it depends on the rest of the party, if they're all well played full casters then, yeah, it can work.

Otherwise, no.

[Vexous]

It really all depends doesn't it? Are you and your table playing the game, or the system?

If you're all interested in the story than of course it can work. The old Baldur's Gate video games are a perfect example of a story along those lines. One mythic character surrounded by a party of regular Joes. Although the gameplay wasn't anywhere near what we have with mythic the storyline certainly was.

If you're worried about balance and adhering to the module as written, well, you're hosed. No, its not gonna work. Most likely the other players are going to wonder why they don't have those shiny godlike powers long before the many other problems of "balance" crop up.

[blahpers]

Depends. Is it a rogue?

(Kidding! Kidding!)