Holy shit people, I actually just realized something.... you could be completely free of the Tadpole just by using the 5E spell 'Reincarnate'. And it's only a 5th level spell, too, which means even Shadowheart could cast it at level 9. Ha! No wonder they didn't include that one in the game... Gale and Astarion were right all along! You just need a good Cleric, which are readily available in Baldur's Gate, possibly even more minor towns or temples, and a decapitation ( Purely symbolic though, you don't actually have to get decapitated first for this to work ).
Well, I sure hope nobody attempts to turn the game's plot into an actual 5E DND campaign or else it's going to get completely unraveled by level 9.
Raise dead would be enough as the encounter with the cultist in act 1 shows that the tadpole leaves the body after death for some reason. And even if yours does not, being dead allows for far more invasive and successful methods of extraction.
So with Withers on standby curing the tadpole would be a matter of minutes and a few hundred gold coins.
But Larian decided that the tadpole is this awesome powerup mechanic you are not allowed to remove.
Well, you could potentially fabricate some reason as to why the tadpoles leaving only happened once, or sometimes, or it's too entrenched in your case, and so on and so forth. Raise Dead's description also say this:
>"This spell also neutralizes any poisons and cures nonmagical diseases that affected the creature at the time it died. This spell doesn't, however, remove magical diseases, curses, or similar effects; if these aren't first removed prior to casting the spell, they take effect when the creature returns to life. The spell can't return an undead creature to life.This spell closes all mortal wounds, but it doesn't restore missing body parts. If the creature is lacking body parts or organs integral for its survival--its head, for instance--the spell automatically fails."
So you could also argue that these more successful methods of extraction would destroy too much of the brain tissue that the tadpole already fully attached itself to and thereby prevent resurrection. Netherese magic involvement likewise certainly qualifying as a 'magical disease', and you've got the cherry on top of the cake. No such caveats or issue when it comes to Reincarnate, though, since all it needs is a soul and a piece of the old body to create a brand new body for the soul itself, head, brain matter, and everything.
