Evolving is the combining of same cards into a more powerful version.
A card will begin in its first form, there is then the second form, third form, and final form. You reach these forms by combining a card of the same type. For a simple example I will take Baby Dragon. Baby Dragon is a demon alignment card, when you combine another Baby Dragon card with Baby Dragon, it becomes Baby Dragon+. If you combine a Baby Dragon+ with another Baby Dragon it will become Baby Dragon++. If you combine it with another Baby Dragon it will become (Hatchling) Baby Dragon.
It is very important to not the (Hatchling) signifies it's in it's final form. You can also identify what form a card is in by looking at the orbs in the bottom right of the card. However many orbs are lit signifies which form the card is in. A card will also be bumped up one level in rarity.
|(Hatchling) Baby Dragon|
When you evolve a card it will hold 5% of it's current attack/defense power and take it with it to the next phase. If a card is enhanced (leveled) to its max before Evolution, it will retain 10% of its current stats.
Because of the way cards are evolved you can use up to 8 cards to evolve, this is done by combining cards into two of the + Versions before merging them. The ++ Version will then retain the stat boosts from each of the cards. Finally you can merge two ++ Versions into its Final Form.
There are currently 5 Common styles of evolution:
4Max: Uses four cards total, maxes each card to full level before enhancement.
6-2: Uses six cards total, only maxes the two ++ forms before enhancing into Final Form.
6-6: Uses six cards total, maxes the + and 1 normal form before combining into the ++ form. Maxes both ++ forms before evolving into Final Form.
6max: Uses six cards total, maxes each card to full level before enhancement.
8max: Uses eight cards total, maxes each card to full level before enhancement.
There are other types of enhancement but they are less common to use. The difference in style of enhancement changes what percent of a cards full potential it will reach. An 8max will reach 100% of its potential. A 4Max will result in roughly 96.5% of the full enhancement. A 6-2 will be about 97.8%. A 6-6 will be about 99.5%. A 6max will be about 99.6%. An 8Max will result in a 100%.
These numbers are trivial depending on the rarity of card. I always recommend on a card that begins as a Rare do a 6-2. If a card begins as a High Rare do a 6-6 or 6max. If a card begins as an SR or SSR I'm a firm believer of 6max or if you can attain 8, 8 max.
I found this chart on Rage of Bahamut Forums. It was originally posted by Mcgrady56. If you look up a cards 8max stats you can multiply them by these percentages to see final stats.
8-12: 99.925% 7-12: 99.813%
8-11: 99.888% 7-11: 99.775%
8-10: 99.850% 7-10: 99.738% 6-10: 99.625%
8-9: 99.813% 7-9: 99.700% 6-9: 99.588%
8-8: 99.775% 7-8: 99.663% 6-8: 99.551% 5-8: 98.502%
8-7: 99.738% 7-7: 99.625% 6-7: 99.513% 5-7: 98.464%
8-6: 99.700% 7-6: 99.588% 6-6: 99.476% 5-6: 98.427% 4-6: 96.629%
8-5: 99.251% 7-5: 99.213% 6-5: 99.101% 5-5: 98.052% 4-5: 96.592%
8-4: 98.783% 7-4: 98.764% 6-4: 98.727% 5-4: 97.678% 4-4: 96.554%
8-3: 98.333% 7-3: 98.296% 6-3: 98.277% 5-3: 97.303% 4-3: 96.180%
8-2: 97.865% 7-2: 97.846% 6-2: 97.809% 5-2: 96.854% 4-2: 95.730%
8-1: 92.509% 7-1: 92.491% 6-1: 92.453% 5-1: 92.266% 4-1: 91.985%
8-0: 87.135% 7-0: 87.116% 6-0: 87.116% 5-0: 86.910% 4-0: 86.629%
Analysis: 6-6 evolved High Rares hold a great amount of their value. A 5max has such close stats that you could reasonably sell a 5max as a 6-6 without the buyer noticing. It also shows that unless you wish to do a 6max there is little reason to use 6 cards in evolution. There is also virtually no reason to do a 7 card evolution. Finally it shows that anything less than an x-2 is virtually worthless in the long run.
On Rage of Bahamut Forums I found these picture diagrams created by Zebriah. They are really well done. These diagrams show via picture how certain evolutions
Eight Card Evolution:
Seven Card Evolution:
Five Card Evolution:
Four Card Evolution:
Hopefully these help anybody who previously didn't know what the abbreviations meant. Thank Zebriah from Rage of Bahamut Forums for them.