Honestly, the western release isn't that drastic of a departure from the original version, though the changes Working Designs made are definitely noticeable to someone who has played both versions. The following is a list of all the differences I'm aware of.
Differences between the Saturn and PSX ("Reprogrammed Hope") releases
*Two extra bosses, Reaper and Geluve, are not present in the Saturn version. Reaper is a hidden boss accessible after the first Megido fight if you haven't yet used any continues, and Geluve is an alternate final boss if you face Serah and then choose to restore Edo.
*Some background elements are removed from the PSX versions to free up memory and alleviate slowdown. Notable among these are the highway overpass in the second stage and some background layers in the first and fifth stages.
*The Saturn version also seems to have significantly "cleaner" graphics with less jagged edges and aliasing, particularly on rotating and scaling sprites. Not surprising considering the Saturn was primarily designed with 2D graphics in mind.
*The Japanese PSX version has significantly longer load times and occasional "loading zones" where the game noticeably pauses to load from the disc.
*The Saturn version had a hidden options menu (accessible by holding X, B and Z and pressing Start at the Treasure logo). This was made inaccessible in the PSX version, probably because the ability to resize the characters' sprites often led to the game crashing. The Working Designs version restores it, albeit making it more difficult to reach.
*The Saturn version seems to have less slowdown and load times overall. The Gargantuan and Serah battles in particular have a substantial amount of lag on the PSX version when being run on a PS2 or PS3 through emulation (though setting the system to use "Fast disc speed" seems to alleviate this).
*The save system works differently on the Saturn version. Rather than being the option to save in between each stage, one must choose not to continue after dying. After that, they will be able to reload their game and continue at the beginning of the stage they died on.
*The control system is considerably different between the two versions to accomodate for different controller layouts.
Differences between the original releases and Working Designs' version
*The Working Designs release has two variant disc artworks: One depicting Hal and one with Megido. The manual's cover is also embossed with foil as Working Designs was fond of doing.
*The FMVs were re-encoded to make them less grainy and artifacted.
*The memory card save icon was given a slight animation.
*The Working Designs version reworks the controls to take advantage of the Dual Shock controller. For instance, you can now activate Parasite Bomb by pressing L3 and R3 at the same time, or power-dash by pressing down L3 as you move.
*The tutorial room music was removed for unknown reasons and replaced with another song from later in the game.
*The dialog and voice were all translated. The voiceovers are decent enough, though some poor audio mixing makes the voice samples extremely loud in comparison to everything else in the game. The translation is also a major point of controversy among fans, as it significantly tones down the Biblical references and introduces a lot of Working Designs' distinctive (and often lowbrow) humor. A list of name differences and their references follows.
|Shyna Nera Shyna||Sinna Neutlarva Sinner|
|Hal Birthclod||Har Birthclod|
|Megido Birthclod||Megiddo Bithclod|
|Zohar Metatron||Zohar Metatron|
|Zohar Sandalphon||Zohar Sandalphon|
|Dynamis||Dynamis06 (Could also be a reference to the Bosporian queen)|
|Pablo||Paulus (Could also be a reference to the Roman jurist)|
|Delia||Delilah the Beauty|
|Cypher Za/Ha-Zohar||Sefer Za/Ha-Zohar|
*Some other images were censored slightly. The shop rabbit no longer smokes or appears with a burning cross on the final stage (instead being edited into a dragon).
*Enemies seem to deal about twice as much damage in the WD version, making the game significantly harder. Most bosses also have less cash then they did in the Japanese versions (usually about half).
*The shop has undergone a significant overhaul. In the Japanese version, all Parasites have the same prices at the same levels. In Working Designs' version, they are all individually priced and generally much more expensive. A chart follows.
On the plus side, every purchase at the shop includes a free 30 Spirit bonus in the WD version!
*Similarly, Mana and Fatima powerups from the shop cost more in the Working Designs version. In the Japanese versions they cost 100 and 50 credits respectively, while in the Working Designs version they cost 150 and 100.
*Probably the single most controversial change is the addition of an energy draining mechanic. Rather than simply having your Spirit energy deplete when hit with an attack of the same attribute, the Working Designs version is reworked so that your weapons will drain your Spirit bar when in use. Additionally, hitting enemies with a same attribute attack will not only drain their Spirit, but will refill your own reserve. This has the unfortunate side effect of making many of the weapons rather useless due to their high energy costs and making some battles, particularly the fights with Zohar and Za-Zohar, much more difficult battles of attrition.
*The save/loading screens were simply black with white text in the Japanese release. Working Designs' version adds some stills from the opening FMV to make them more visually interesting. Additionally, they made it possible to save and load from a memory card in either slot instead of just Slot 1.
*The Japanese version had a bug in the second stage. After knocking the walker off the truck it would sometimes not respawn, making it impossible to continue further in the game. The Working Designs version fixes this.
*A Lunar 2 preview video was added to the game. To view it, hold L1 as you boot up the game.
*The continue system was overhauled a bit. In the Japanese versions, you get nine continues per playthrough. In the Working Designs version, you get nine continues which do not replenish on subsequent playthroughs. This essentially means you have a limited number of chances if you wish to clear all five paths.
*The Japanese version had a button code (Up, Up, Down, Down, Left, Right, Left, Right, X, Square, Triangle, Circle at the pause screen) that would give the player 9999 coins and a Level 6 Sloth, Gluttony and Lust. The Working Designs version removes this.
*The Status screen was added to the game. The Status menu lets you keep track of all the "paths" you've cleared (one for each of the four ending branches, plus a fifth for defeating the Reaper). The Options menu from the Saturn version is returned, but is now only unlocked after all five paths are cleared. This results in you paradoxically having to beat the game at least four times on "hard" mode to unlock easier difficulties...
*Two minigames were added to Working Designs' version: Zohar appears on the credits roll and can can be controlled by the player, enabling you to destroy Polly Peepers and Spectres for a few minutes. The other is a two player head-to-head mode called "Super Core Fighter" where one player controls Shyna and the other Zohar as they try to defeat one another within a two minute time limit.
So to conclude: Which version fares the best overall? Honestly, I'd say the Saturn version is my favorite to play, as it's the most technically sound of the three and it definitely looks the nicest owing to its stronger 2D hardware. However, the Playstation version is also worth checking out for its added bosses, so it's all a matter of personal preference. There's also a fan edit of the WD version in the works that attempts to restore the original story and gameplay while retaining Working Designs' improvements. If that ever gets off the ground, I'd say check that one out!