When it comes to actual gameplay, Syder is impressive. The controls are smooth, and the addition of subtle gravitational pulls against your ship adds an element of realism (not that I know what it feels like to steer a real starship). The virtual directional pad on the left is adequately sensitive and the Special Weapon and Flip buttons are comfortably placed.
Some dedicated fans of side-scrolling shooters might be wondering what a Flip button is for. Well, that is the unique thing about Syder. The game actually scrolls both to the left and the right. This makes the game significantly more difficult, since enemies are swooping in and firing from all sides. This isn't necessarily a bad thing, though. In fact, I enjoy the unique challenge that this multidirectional gameplay offers. Your starship automatically fires continuously, so it's your job to simply point your ship at the baddies and evade their fire, no matter what direction they're coming from.
As you kill more enemies in Syder, you earn more points. And as you earn more points, your Special Weapon meter rises. Once you fill this meter up to a certain threshold, you'll be able to unleash a powerful attack that is unique to your particular starship. For instance, one of the ships' special weapon is a Gravity Well, while another's is a Hyper Beam.
Also scattered throughout the game are minor power-ups for your regular gun. This is where I think Syder has the most room for improvement. Everyone loves building up their weapons in these sorts of games, but unfortunately, Syder's available upgrades are few and often insignificant. Perhaps in future installations, we'll see some of the screen-shaking cannons and bright laser beams that these graphics deserve.
Overall, Syder Arcade is a fun and incredibly smooth game that should be a worthwhile buy for fans of old-school, spaceship-themed sideways shooters. Its multidirectional gameplay is notable and its controls are impressive. The biggest thing it needs is a wider assortment of upgrades and vehicles.