Seth isn't a Jeigan. He's an Oifaye. And a damn good one too.
EXP that goes to Seth is much less missed compared to the starting prepromos on other FEs, since Seth's growths are actually good. He has the best growths among his fellow starting prepromos, save FE9's Titania.
He can solo the game if you want, and even if you don't, when used sparingly he is a great problem-solver early-game, and a more-than-competent team member late-game.
Hence, he's a great character, as long as the player isn't newb or fool enough to overuse him from the start. Which is their problem, not Seth's.
There is no hatred so great as that of a man who has been made to love a woman against his will. -Hercule Poirot Proud Winner of CyberSD's Fire Emblem Trivia.
Let's say we compare Seth directly to another good character, Franz. By 'compare directly', I mean that we give them the same kills and the same resources. In earlygame, Seth is way, way better than Franz. in midgame, Seth is still significantly better than Franz. In lategame, Franz may have caught up and be performing equally, but it's not very likely.
And one key difference between a Jeigan like Seth and a growth unit like Franz is that in order to get to 'Franz being good', you have to deal with his mediocre phase to train him. Seth is free, does not need training to kick ass, and is at lower risk of getting RNG-screwed.
I love Seth. And Titania. And Marcus. All those great already promoted EXP drains they force to take up a lot on your team.
Aha, you're all forgetting a key feature of Seth's reportoire that makes him truly great.
The incredible early game, the average end game, the anima lord support, the versatile class, all merely adds up to make Seth into high tier. What bumps him up into god tier, is the fact that he functions as a metal detector.
In lategame, Franz may have caught up and be performing equally, but it's not very likely.
I have trouble seeing why Franz doesn't have a better (let alone equal) lategame to Seth. FE8 curves exp hardcore (+3.33 for each level down you are per kill) such that they'll only be a couple levels apart by the end, and Franz's stats are quite a bit better at similar levels. In particular, I remember Seth having trouble doubling enemies with decent speed (Heroes, Rangers, SMs), Franz doesn't have this problem.
Don't get me wrong, Seth is still awesome and I agree he's better than Franz overall.
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