As far as the Gradius series is concerned this is my favorite entry. I'm not going to sit here and make up a bunch of reasons why I like this game more than all of the other titles. I think constantly comparing games to similar titles doesn't accomplish anything. I mean if that was the case why bother playing Gradius III when you could just play Gaiden and why play Gaiden when you could just play Battle Garegga? It's complete nonsense and I think it does gaming a huge disservice.
Gradius Gaiden is simply a great shooter. Unfortunately it's also more difficult to attain than most of the other entries in the series. It's available on the Gradius collection for PSP but unless you own a PSP and enjoy playing 2D shooters on it you're out of luck. The only other option is the import-only Playstation 1 version. If you haven't already I highly recommend seeking out an import or modded Playstation 2 console. Some of my favorite import titles like Shinobido Takumi and Earth Defense Force 2 are available on it. Unfortunately I should point out that stage 7 runs very slowly on the PS2. Not sure why that is and the rest of the game runs quite well but eh there you go.
This game is divided into nine stages and should take somewhere north of 40 minutes to beat. Each stage covers a different theme and is always side-scrolling. Some sections of certain stages can scroll vertically as well. Gamers familiar with other Gradius entries will recognize familiar themes. One stage is devoted to Moai statues(like the ones on Easter Island). There's a boss rush towards the end of the game. There's also a speed section in one stage with lots of narrow corridors, enemy cannons, and trap-doors.
Unlike the other entries however this game offers four selectable ships. Series favorites Vic Viper and Lord British are available but they're joined by two ships known as the Jade Knight and Falchion Beta. Each ship has their own set of weapons. After selecting a ship the player can choose their own shield. Shields are a popular aspect of the Gradius series in that they can catch most bullets but they're balanced out by some negative aspect. One shield might allow the ship to take three hits but it's so large that simply flying close to a wall will cause it to disappear. One rather unique one actually makes the player entirely invincible for a few seconds. It's rather unfortunate that my favorite one from Gradius III doesn't make an appearance. This shield not only lets the ship take multiple hits but also shrinks it. I guess since it had no real weakness it was really unbalanced...oh well.
After selecting a shield the player can edit their weapon gauge. For those not in the know the Gradius series is notable for offering a twist on the traditional powerup system 2D shooters have. At the bottom of the screen all of the available weapons are arranged. By grabbing red powerups the player can cycle through these weapons. When the player gets to the one they want they can press the button to equip it. Usually this powerup system is arranged in the order of: speedup, missile, spread(a weapon that covers more ground), laser(a more powerful weapon with less range), option(adds a glowing orb that follows the player and adds more firepower), and shield. Anyway in the edit gauge mode the player can decide when the various weapons can be accessed. Not a fan of the missiles? Move them to the very back so it takes more powerups to get to them. Prefer laser to spread? Again just move laser forward and spread back. There are more than enough powerups to go and I'd always put the speedup to the front(you need at least one speedup to have a chance at survival).
While each stage is fairly short all of them are composed of interesting concepts that don't become repetitive or stale. Just when the player has gotten a handle on things the stage will end and the boss will appear. The locales will be familiar to long-time gamers like an ice stage at the very beginning of the game. The game throws a few curveballs and does some truly clever stages. Stage 7 for example is more or less a remake of the first stage from the first Gradius, with a basic array of rocks, volcanoes, and the standard mix of enemies. What's different here is that a black hole opens up just behind the player and sucks everything in. So all of those rock placements and volcanoes will crumble and fly at the player. Another stage has crystals everywhere. Aside from dodging them the player also has to contend with lasers that bounce off the crystals in a variety of angles. Despite the constant changes in concept the game still has a steady progression in difficulty and the challenge ramps up nicely thanks to a rank system.
When a shooter fan thinks of a rank system they generally think of an extreme example like Battle Garegga. This is all well and good but for a series like Gradius which doesn't rely on intricate scoring systems it's all highly unnecessary. Gaiden keeps it simple by merely having enemies fire more bullets and bosses gaining stronger attacks. Players who survive long stretches of the game without dying are also more likely to run into option-stealers. These guys hang out at the back of the screen for a few seconds before making their move. Since your options follow you wherever you go it's fairly easy to get them out of the way. However the option-stealer is more likely to show up in areas where you're already getting assaulted by enemies from all different directions.
Compared to entries like Gradius III Arcade and part V, Gaiden is a fair bit easier. It retains the simplicity of the older games and at least on the normal setting is a fairly easy ride up until the final stage. That said there's still plenty of challenge due to harder difficulty settings and the fact that the game offers up multiple loops which substantially increase the intensity and ferocity of enemy attacks.
Gaiden's greatest strength is in its variety. As mentioned before each stage has a particular theme and the enemies as well as the boss tend to follow suit. All of the bosses have unique methods of attack and sometimes survival is more about expecting something strange rather than dodging wave after wave of bullets. Couple this with the impressive level design and each stage becomes an experience that is incredibly well put-together.
The mechanics of this game are absolutely wonderful. Unlike most shooters where a stationary cannon can fire in any direction, the cannons in Gaiden will turn towards you before they fire. Larger enemies that move about the environment move so fluidly that you can approximate where they're going and react accordingly. Another important aspect is that the ship's hitbox is very reasonable. Weaving in-between bullets and getting through near-death situations is never a problem and collecting powerups that are close to walls is never a problem.
For a game that frequently uses a variety of methods in attempting to defeat the player the proper combination of audio and visual cues are necessary. Gaiden does an excellent job of covering both of these aspects. Attacks that fall outside the range of mere bullets(like lasers of all flavors, pulse waves, etc) always give some visual or audio warning so the player knows what to expect. This is very smart game design.
Gradius Gaiden is basically flawless and very entertaining. It's shallow compared to a number of contemporary shooters but on the other hand it's more accessible. It shows creativity in both level and enemy designs but never runs concepts into the ground and keeps an excellent pace throughout. As far as I'm concerned this game is a classic and a necessity in every 2D shooter fans library as it has enough for everyone.