Kyogre * ($30.00)
~~~
Tyranitar ex [Delta Species] ($15.00)
Well, considering the prices, it sounds like a good deal to me. However, price isn't the only factor.
• Condition of the Kyogre * [Is it mint?]
• Sentimental Value [Did you pull the Tyranitar from a pack? Did you use it in a tournament? (For instance, my 1st Edition Jigglypuff is only worth 18¢, but it was my first card ever, so I'd never trade it]
• What you plan to do with it [Are you planning to sell either card for money? Are you going to use them for a deck? Collection?]
So, consider those carefully before you make the trade.