A card's rarity will tell you how strong a card is and how hard it is to get. Take a look at this schematic to help:
N, N+, N++ -> NN
NN, NN+, NN++ -> R
R, R+, R++ -> RR
RR, RR+, RR++ -> SR
SR, SR+, SR++ -> SSR
SSR, SSR+, SSR++ -> LR
LR, LR+, LR++ -> GR
At first sight it looks a bit complicated but it's really simple. Take the basic rarities from N to LR: N, NN, R, RR, SR, SSR and LR. Any card you get from an event or draw from a CP, etc. will be one of that rarity. The other ones (N+, N++, NN+, etc.) are for when you evolve cards.
After evolving, a card it will change its picture and increase their stats. You can get some more info in tutorial but it's not complete. If you take two of the same N cards and use one as evolver to evolve them it will became N+ with 2/3 points in the bottom right corner of the card. Evolve that card it once more and it will become N++ with 3/3 and finally at stage 4 it will be NN with S instead of ball points. An S means it reached max level and can't be evolved any more. Always remember that any rarity of card with S will be weaker than the same rarity with one ball point and that you cannot get a LR with one ball point.
Enhancing is very important in Deity Wars. By offering some cards and gils to another card you can increase the level of cards. There is some information in the tutorial but most things are missing. There is also much information from players but because every card is different by itself it's hard to say a specific way to complete enhancing guide.
Kujata can be used as a more efficient enhancer as well as Friendship Medal cards which are given to the players with the most friendship medals at the end of the week.
If you enhance a card to its max level it will give you a certain material (from a slot near the bottom of the card above the skill section, usually an attack material) depending on the rarity of card. If you evolve a card you will lose its level, but skills and materials in the card will stay. The best way to get the best result from cards and materials is to level every card to the max in every evolution stage from stage 1 to stage 4 because once you open the first four slots, the fifth one will open and give you a very good material (also depends on the rarity).
In other words if you get a N card and enhance it to level 20 (the max level) you get a material, then you evolve it to stage 2, again enhance it to level 20 and you will have a N+ card lvl 20 with 2 unlocked material slots and 2 materials in your gift box waiting for you to claim. If you continue like this at stage 3 and stage 4 (enhanced to lvl 30 because it's now an NN card) you will get an extra reward for completing every material slot and an extra reward for collecting. Collecting will give you reward at 1st, 4th etc.
Because enhancing every card at every stage is expensive we recommend you to do so only with cards of rarity RR and higher.
Remember that the gil cost for enhancing depends on the target card's level, not the amount of cards that you are using to enhance it. So always try to use all 10 cards to enhance.
Base card (the card you want to keep i.e. the card you are evolving) + Evolver (the card that will be deleted and used to upgrade base card from stage 1 to stage 2 etc.)
Remember to always keep the Base card as the card with most slots open for when you use materials on it which is given from leveling cards to their max level.
Full Moon RR and SR are very useful cards that can be used to evolve almost anything. Full Moon RR is usually given out throughout events and Full Moon SR is usually given out upon completion of an event. Full Moon RR can evolve any cards RR and lower but it is best to use it only on RR (and maybe R) cards. Full Moon SR can evolve any cards SR and lower and it is best to save it for an SR card. There is currently no Full Moon card capable of evolving an SSR card. Full Moon and Kujata cannot be evolved.
Remember that a stage 2 card + a stage 2 card won't become stage 4 so NEVER try it. But Base card at stage 1 + evolver at stage 2 will upgrade your base card to stage 3, which is very useful if you get a card with more slots.
You can get extra ATK and DEF if your evolver card have some levels or materials in it. The numbers are currently unknown but for materials it's supposed to be 5-20% of material stats in the evolver card, so for example if you use an evolver with three +1000 ATK materials equiped your base card should have a boost of 150-600 more attack after evolution.
Remember that evolving will put your card back to lvl 1 but it will keep any material and skill it has and that LR cards can only be obtained by evolving SSR.
Many people have their treasures stolen from them due to lack of DEF Power so it is important to know how to build a good defence deck. A few people use the automatic selection to create a deck which has the most DEF Points but it is usually not the best that they could make. Others neglect their deck or pay very little attantion to it.
A very popular method of defence is to put together a collection of cards from a single element which have defence raising skills. A lot choose to have a deck full of N Necromancer cards. This works very well on beginners but has limited defence against more powerful players. So a few have NN Necromancer decks which keep out lot more would-be attackers. Some have different cards of the same element with similar skills. You ideally want a deck full of cards of rarity R or higher with the same element that all have defence raising skills. Now you need a lot of MP to do this so it is important to get many allies.
Another thing you can do is to equip your cards with defence materials. You can get these by levelling up a card to its max level. Some cards will give you an attack material, some will give you a defence material and others will give a special material. Another good idea is to regularly check your DEF MP Points to see if you can fit another card in.