1. How does the card stand on its own? Is it good, bad, or has potential? Is it worth playing?
Gengar Lv.X is somewhat nice on its own. Its Poke-power, Level Down, can be pretty annoying against most decks that rely on Lv.Xs as attackers. Why? That's because the Poke-power actually
Level Downs the opposing Lv.X, where it is then shuffled back into the opponent's deck. Moreover, when you level down a Lv.X using Gengar Lv.X, you can choose any opposing Lv.X you want, whether it is the active or on the bench.
Gengar's attack is good too, especially in spread decks. It can do 30 to all of your opponent's Pokemon with damage counters on them. Since both Gengar SF and Gengar AR have a way to spread damage around on the bench, Compound Pain can actually come into good use from time to time. Of course, cards like Nidoqueen and Garchomp C get through this, which is sadly a problem. This is often the reason why Gengar is often used mainly for its Poke-power. Thus, I would say Gengar Lv.X is worth playing and can be good on its own, but you need to make sure you run a Gengar since after all, this card is a Lv.X.
2. What popular metagame decks is it used in?
Gengar Lv.X is pretty much used in any metagame deck right now that uses a good Gengar of some sort. These Gengar decks include Cursegar, Mother Gengar, and Gengar C. Cursegar uses the Gengar from Arceus that has a hit an switch ability, while Mother Gengar and Gengar C use the Gengar from Stormfront. In these three Gengar decks, Gengar Lv.X has been shown to come into some nice use. As mentioned, one reason is because Cursegar and Gengar SF have a way to spread damage; yet, another reason why Gengar Lv.X is used in these decks is because Gengar Lv.X helps boost Gengars' HP from 110 to 140, making the Gengar you run harder to take down.
3. What combos can you use it with? How so?
Obviously, I'd use Gengar Lv.X with either Gengar AR or Gengar SF. My intent with Gengar Lv.X is that I want to be able to have a nice way of spreading using Compound Pain after spreading some damage counters around with the Gengar I run. I'd also use Gengar Lv.X to boost the HP of my Gengar so that my opponent will have a harder time taking it out.
Well, yeah, I'd pretty much use Gengar Lv.X as it is being used nowadays in competitive play.
4. Give it a rating, and explain why you would give it that rating.
I would give Gengar Lv.X a
3/5. It is certainly a nice addition to many Gengar decks out there right now. It has the ability to throw back an opponent's Lv.X back into his or her deck, and it can have a nice way of spreading too. The problem with it though is that nowadays, many seem to use the other Gengars a lot. In fact, the Gengars can be so useful that you may not even need to use Gengar Lv.X for the match. That's why Gengar doesn't seem to be not that overused.
5. How's the artwork?
OK, this one of the best artworks for a Gengar ever! I really like how Gengar is popping out of the screen and is literally beginning to unleash an attack. Now this is how a Lv.X should really look like that's for sure.