1. How does the card stand on its own? Is it good, bad, or has potential? Is it worth playing?
Tyranitar Prime can be good on its own. Literally, he has quite some nice attacks. It can spread 20 to all non dark Pokemon, hit for 60 without going through Poke-Powers or Poke-Bodies, and it can hit for 120 damage for four. Well, it may look expansive, but DCE comes into great use with this card, making it slightly faster. Furthermore, if you can give it an Expert Belt and two special Darkness Energies, you can literally hit for 160 damage. Thus, I would say Tyranitar Prime can be quite good on is own and it is somewhat worth playing.
2. What popular metagame decks is it used in?
There are no major metagame decks that use Tyranitar Prime at this very moment; however, if it were to make it into competitive play, I would say there would be a deck that would be built around it. For now, of course, we may never know if Tyranitar will make into becoming a metagame deck.
3. What combos can you use it with? How so?
Literally, if I were to build a deck using this card, I would have to build it so that it would be the main focus. I would run cards like Claydol, Uxie, Azelf, and maybe Unown G. I would consider about putting Nidoqueen in there as well. For a starter, I would use either Spiritomb to prevent early game Rare Candies from the opponent or Sableye since you would literally be playing a dark deck, and Sableye would fit well to both set up or even donk. Now in order to counter something like Donphan, probably Tyranitar's nemesis, I would run Frost Rotom RR. I would use it by using its Poke-Power to turn it into a water type. Then, I would make sure I have a DCE and a water on it and then use the second attack to hit for 40 plus 10 for each {C} energy in the defending Pokemon's retreat cost. In this case, since Donphan has a retreat cost of 4, it would do 80, times 2 for the weakness, and that would do 160 damage, which knocks out Donphan. Thus, Frost Rotom can be a great backup attacker when Tyranitar has to go up against Donphan.
4. Give it a rating and explain why you would give it that rating.
I would give Tyranitar Prime a 4/5. He can be quite a good card all right. He has very good HP, a great ability to hit very hard, great resistance, and a type that can easily take down a Cursegar deck. The problem with Tyranitar is that it has weakness to Donphan, a somewhat high retreat cost, and the fact it may most often attack for 3 energies means that it is a tad to slow in this format. Regardless, I think Tyranitar is quite a good card.
5. How's the artwork?
Man, I didn't see a great artwork by Wataru Kawahara in ages. This definitely is a great art for Tyranitar. The glint in his eye really shows that it's saying, "I'm ready for a battle!"