There are many changes from the first title, The Silver Star, to the second, Eternal Blue.

Here are a few changes:

• You can hear characters' feet hit the ground as they walk in battle scenes.
• There are more options, accessible by the previously unused Start button.
• Spells look a little nicer when performed.
• The "Flee" command, which allowed characters to dodge attacks without running, was removed. It was replaced by "Defend." Players can defend themselves (same as fleeing) or defend others.
• Saving is now possible inside houses and buildings.
• There are much more animation sequences.
• Animation sequences have more anime-like movement.
• The original theme song was taken out of the beginning. There are two more drippy slow songs accessible on the CD, but they are not at the intro.
• Tactics, editable preset choices for each character in battle, similar to Macros in Phantasy Star IV, have been added.
• In battle, the "Nall" command was omitted. Now the enemy names are already listed when you first go into battle.
• The instruction booklet, black & white, is now printed in full color.
• The Eternal Blue package weighs approx. 1.6 oz more than The Silver Star.
• Ruby, the dragon descendant and counterpart of Nall, can now attack and kill off enemies who are left with only three hit points. (Later in the game Ruby can take off six.)
• Items are arranged differently in character's inventories.
• There are now two different experience points won in battle: regular experience and Magic Experience points.
• It costs to save. Depending on how far you are, it will cost a certain number of Magic Experience points every time you save your game.
• You can use Magic Experience points to upgrade a set of spells of a character. Once the group of spells gets to a certain level, you will learn a new spell in that group.
• Saved game blocks are arranged differently on the Sega CD backup memory.
• Eternal Blue is now directly compatible with the Sega CD Backup RAM Cart. Games can now be saved and loaded from the internal Sega CD memory or the optional cartridge.
• Battles are now different. You first choose what the party as a whole will do. (AI, Command, Tactic, or Run.) If "Command" is chosen, characters can be controlled manually, individually

The order of the characters in the party is changed so the character order can be physically rearranged. In battle, characters run differently. As one reader notes, "In Lunar I, they disapeared according to their agility, and in Eternal Blue, most of the time they danced around the screen like damned fools which really got to be irritating!" The sequel may have unsuccessfully attempted to introduce some more strategy to fighting.

Music & Dialogue

There are also a number of dramatic changes concerning the music. The music on The Silver Star loaded directly off the CD as audio (which also means all of the music are also playable on standard CD players), whereas the music on Eternal Blue is compressed. This has its advantages (much more music and dialogue will fit on one CD, "secret" audio tracks will not be audible to anyone unless they are playing the game) as well as its disadvantages. Its main disadvantage is it makes a much longer loading time. (Keep in mind the first title had very little loading time when it came to entering a battle sequence or moving around in dungeons.) When entering a standard battle, there is a considerable loading time of a few seconds. The same is for leaving battle, moving into or out of a location, and sometimes (but not often) while entering or leaving a room. I found this extremely annoying (it doesn't help when you're stuck in a dungeon and short-tempered) but after a while I got pretty much used to it. Another disadvantage is the music isn't quite as clear, although it still has good quality.

Ratings: Bad Humor

The game features a lot of humor elements, which gave the original Blue Star an MA-13 rating from Sega's Videogame Rating Council, or VRC. The game was rated MA-13 ("Parental Discretion Advised") because of some dark humor in the game. One good example is a woman in a trading village who, when talked to, says, "I'm a merchant of sorts too.. but you're too young and sweet to know about the goods I sell.." By the time Eternal Blue was released here, there was already an industry-standard rating board, the Entertainment Software Rating Board (ESRB). So, Eternal Blue, although it did contain the same amount of bad jokes, if not worse (it even had the word "damn"), was rated on a different scale.It recieved a "K-A" (Kids to Adults) rating (which recently has been renamed "E" for Everyone). The VRC was stricter on ratings than the ESRB is now, although some comparibly foul language in Silpheed did slip past them. However, on the back of Eternal Blue, the newer game that recieved the K-A rating, the ESRB does state that the game contains "mild language."