Laharl, with a level of 1,500, can easily destroy planets, and is faster than light. A level 20 character can comfortably wear 100 ton underpants, and can move faster than the eye can see, fast enough to leave an after-image.
Baal, at his absolute worst, is level 4,000. He is the strongest character in the series, short of the deity whose name I forget.
Even if through some arcane sorcery Link were able to kill Baal, Baal is undying, and he has numerous back-up bodies he can use.
Link has no chance at all.
The entire Legend of Zelda verse has no chance at all.
Well, he'd certainly make Baal laugh. I mean, a green tunic wearing elf swinging a sword in vain...
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"To all visitors from Transylvania looking for the head of Voivode Dracula: Yes, we have it. Yes, he's dead. No, you cannot see it. No, he will not return and invade you again. It has been over thirty years, please stop pestering us."