Well, that's it for season 4. I'm sad to see it go, for it was easily my favorite season. However, I found myself disliking the season finale, and the Lich in general, and here's why:
Let's start with the obvious. The Lich has no personality. Why is he evil? Why does he do what he does? Who cares, right? Now, Flame Princess is a pretty boring character, but she has traits (Easily angered, passionate, niave ect ) the Lich has just...evil...and kind of intellegent in some ways, if that counts as a trait. (I'll talk about what makes a good villain later). But not only that, but the Lich is never a legitimate threat, and here's why. He was defeated by luck. He wasn't killed by effort, or planning, or cleverness. Finn just happened to have the right Deus Ex Machina, in the form of love, to destroy the Lich. That's it. When Finn tried to take down Hunson in the Nightosphere episodes, however, he had to actually think and manipulate. The fact that the hero had to put actual effort into his defeat made him a threat. However, all you need is a really common emotion to defeat the Lich, therefore taking away all of his threat status, and making all buildup of how "scary and dark and epic and powerful" he was basically meaningless.
And now let's talk about good villain motivation. The Ice King feels lonely, and cold, so he has to capture princesses to feel loved. This is an understandable motivation, because most of us have felt unloved at one point or another. Even if this hasn't caused us to do evil things, we can understand where's he's coming from, and therefore can sympathise with him. Have you ever felt like you just wanted to destroy everything for no ****ing reason? No? Exactly. The Lich doesn't just have an unrealistic motivation, he has no motivation whatsoever. He's evil because he is. Now, other villains may seem to have the same motivation. The Joker for example. His only motivation seems to be madness/insanity. However, he also does evil things for the sake of standing out from the crowd, or because he doesn't want to appear weak (I myself have done some morally questionable things for these reasons). Those things we can actually feel, and understand.
And even within his own stupid little archetype, he's not even that great. He doesn't do anything where I'm like "Holy math, this guy is completely detached from all sanity" nor does he really get into the characters face and be a complete jerk to them (ei, Umbridge from Harry Potter or Ash).
But the worst part is, he could have been great. He actually made PB afraid of something, and he destroyed Finn's niave worldview. A big dark and realistic enemy suddenly bringing dark realism to a world of silliness could have been a great character concept, but his lack of personality and whatnot makes him terrible. Actually, maybe I'm not giving him quite enough credit. I did like that he exploited Finn's love for Billy in the new episode. It makes him just a little more threatening, which I can respect. But whatever.
Now, a lot of people have been telling me that the Lich is good because "OMG he's like so mathing evil and evil and evilevilevilevil" Well, being pure black-hearted is no excuse for having neither a personality nor a motivation. Goliad is pure, heartlessly evil, and even more dangerous than the Lich from a certain perspective. She has both a realistic motivation and an interesting personality.
And here's why villains with motivations are scarier. If a villain is evil because why not, there's no relatability. All you need to worry about is how to defeat them. If a villain has a reason, especially if that reason turned them from kind of heart to evil, there's always a threat that you yourself, or the protagonist (Who may or may not have a lot of similarities to you) are but a step away from becoming them.?
"You know what the only difference between me and you is? One...bad...day"
And that's why, in my opinion, the Lich is one of the worst characters in all of Adventure Time, as well as one of my least favorite characters ever. If you care to debate me, do so in the comments.