Finished Genocide route. Wow. That was chilling.

(SPOILER)I remember the moment I entered the route for the first time. I was starting to get seriously bored from grinding enemies with an encounter rate that continuously gets lower and lower. Then the "But nobody came" encounter hit and instantly it was all worth the while. That eerie music, all the random monsters disappearing including helpful frogs and ghosts that used to block paths. And then you slice Toriel in half with just one attack... and she comments on how much you apparently hate her and then she realizes that in keeping you in the ruins she wasn't protecting you from the monsters, but the monsters from you... man that was an indescribable feeling.

And it only gets better from there. Other favorite moments include picking apart the Snowman ("You got the Snowman's Piece."), Buy and Sell in shops being replaced with Take and Steal, the fight screen vs Monster Kid, Flowey's lengthy monologue near the end giving some more insight into how he became the bitch he is during neutral route, and of course the final battle with Sans. Man that was a good fight. Love that kind of challenge. I was a little disappointed with the ending of the route, but eh, can't win 'em all.

The grinds were kind of annoying, but thanks to the AFK encountering trick you can circumvent the boredom at least. Still rather poorly designed IMO.

Overall I'd say the end of Neutral route was still the best part; but other than that Genocide route was easily the most memorable storyline path.