Refess is the most balanced of all the colors. It contains powerful healing abilities, lightly armored soldiers with plenty of offensive and defensive abilities, and by a slim margin, the best SP generation of your four choices. In the Japanese version, Refess is an SP generating monster, so you can expect to see a bit more of that as the game progresses and more expansions are released.

Refess Card Files don't like to see their units go to the Cemetery, and thanks to all the healing and Revival at Refess's disposal, they usually don't have to. The light armor helps, too. While some other colors have better armor, Refess is very consistent. It seems like every card has a little bit, and every little bit helps when it comes to DF. Refess tends to be very average in the AGI department, so expect to be slow against fast Card Files and fast against slow Card Files.

Lawtia is probably the most extreme of the colors, but it can also be the most powerful. If a Lawtia Iczer wins with only 1 LP remaining, his first thought is "all that matters is that I won." In fact, you could say that if he had too much LP to spare, then he wasn't dueling in the spirit of Lawtia. Lawtia units have excellent offensive capabilities. While a few of them have strong defense, they often do almost as much damage to themselves, and their Iczer, as they do to the enemy (but with Lawtia, that "almost" counts for a lot). Lawtia units get bonuses at night, which means a little timing can really go a long way.

The other thing Lawtia is good at is burning the enemy's SP. Killing off a point of SP here or there can really cripple an opponent's strategy, and no one is better at it than Lawtia. Combine SP burn with the night bonuses, and you can see that with a Lawtia Card File, timing is absolutely vital. Lawtia cards tend to have above average speed and range, but only one super fast card and no exceptional archers.

This Sphere is known for fighting, and that means they have big hit points and do big damage. Their Grimoire cards generally do straight damage, and their support cards are the best at giving bonuses to AT. Their biggest advantage however, is not strength but speed. With stronger level 2 cards than anyone else, you'll have a solid fighting force on the field quick. Also, Gowen units have a wide range of AGI values, from slow tanks to lightning fast swordsmen.

When building a Gowen Card File, you'll usually find you have more inexpensive AGI 4 choices than any other color, and those will make a big difference. Gowen cards also have Rankup, which means that when your Sphere Level in Gowen reaches a certain point, your cards essentially get a level up and become a little stronger. This means if you don't have enough SP to pull out a card, you can drop a point or two into your Sphere level and get some quick payoff. To balance out all this power, Gowen has one big disadvantage: defense. If you play Gowen, you can count on having basically no armor or healing. On the plus side, this gives you a bit of an edge against "armor piercing" Card Files, because a lot of their powers won't help against you. In addition, Gowen has some decent SP generation. However, their SP generators are not as easy or as quick to play as Refess'. Overall, Gowen's strategy is simple: take control of the field early, and then hold onto it by hitting your enemy as hard as you can with a balance of power and speed.

Falkow is known as the thinking man's sphere, and has the potential to dominate any game... provided the Iczer plans in advance. Falkow rewards card combos the way Lawtia rewards timing. Falkow doesn't have high HP, but it is one of the best colors for defense. Falkow cards don't do much damage, but they are good at landing their attacks where they count, with a few different ways to target opponents and some very strong ranged fighters.

Technically, Falkow cards have the highest AGI on average, but because a lot of their best fighters are AGI 1-2, Falkow will feel slow if you don't take advantage of its greatest advantage, AGI manipulation. Since hitting first can make sure the enemy doesn't hit at all, increasing or decreasing AGI is the key to making your combos and breaking the enemy's. In general, Falkow card skills and special abilities are among the most versitile, and that means there's a lot of potential for making them work off each other. If your idea of fun is to leverage a variety of combos to control your enemy, you might be able to tap into Falkow's hidden strength.