At this point in time, Soulcalibur is simply a refresher until Soul Calibur IV releases.
Pros
+Resurrection of a classic.
+Great time to be released.
+Easy to pick-up and play.
+Awesome cast of characters.
Cons
-No online play.
-Little reason to play after achievements (e.g. no unlockables).
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Gameplay
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If you were ever interested in a fighter game before, Soul Calibur is no different for the most part. You can run in 8 directions, and it's a basic 1 on 1 match from a cast of 19 or so characters. Each character has a variety of moves, and Soul Calibur maps them quite uniquely. The X and Y buttons control whether you strike across or downward, and B lets you kick while A is your guard ability. A+X is one way to grab enemies, and the move lists are easy to access (straight out of the pause menu) and fun to initiate. Each character has a different level with the ability to ring out your opponent. Your modes of play consist of: Arcade (8 stages of opponents), Time Attack (Timed Arcade), Versus (1 on 1 against a friend), Survival (See how long you can survive), Museum (concept art, videos, etc.), and so on.
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Value
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For 800 MS points ($10) you get mostly the original release of SC on the Dreamcast, albeit no opportunity to unlock the already unlocked... unlockables. You understand right? Anyway, it's a great buy if you have some friends to play against, are looking forward to SC IV and want a refresher, or if you like fighting games (even if you are new to them).