From Dragon Mania Legends (DML) Wiki
The Enchantment Altar is a building part of the Enchantment feature. The Altar is located on the Main Island next to Chronos where it sits upon a circular platform of rounded square tiles, in the center of which is a larger, circular tile, and carved into it is a Viking tribal symbol. Around the edge there are two Dragons akin to Chinese dragons, and between them is a large circular display of two disjointed rings - one large gold ring rotating slowly clockwise and a smaller teal ring floating inside of it, rotating counter-clockwise. Beneath this display is a small round altar with upturned feet, which glows a soft teal within its basin. The Enchantment Altar can only be used after Enchantment is unlocked through leveling three Dragons to Level 16.
Selecting the Altar will bring up three different options, namely ascension , fusion , and enchantment . The last two options can also be accessed by pressing the at the bottom-left of the main screen, and then selecting the Enchantment League option.
See Enchantment for more information
Enchantment is the process through which Dragons of Level 16 or higher enhance their Attack and Health stats and are also granted unique privileges, such as participating in the Enchantment League or engaging in Enchanted Breeding. Enchantment is done through a combination of Enchantment Materials and Enchanted Trinkets.
See Fusion for more information
Fusion is an irreversible process through which identical Enchantment Materials of the same grade and Element are merged together in order to obtain materials of a higher grade. A predetermined number of lower-grade materials and Enchanted Trinkets is necessary for fusing materials. The costs vary in accordance to the quality and Element of the material.
Ascensions is a unique feature, unlocked at Level 50, that allows Trainers to permanently trade their duplicate Dragons in exchange for Enchantment Materials matching the Elements of the traded duplicate. Inside the screen for ascending Dragons, the rules of ascension can be read by tapping the ?, after which the next step is pressing the Ascend Dragon! button in order to proceed to the process itself.
During an ascension, the Enchantment Altar can still be used to fuse materials and enchant Dragons. While fusing materials and enchanting Dragons can also be accessed through other methods other than the Enchantment Altar, ascending can be done only through this building.
From the selection screen that just appeared, the Trainer is allowed to choose one Dragon from all the duplicates that are currently housed on the islands or stored in the Dragon Vault. Duplicates that are in the inventory must first be hatched and will not appear in the selection screen until then. Dragons that are currently busy (breeding, skill training, Elemental awakening and so on) will appear in the selection screen, but will not be eligible for ascension.
The duplicates that appear in the selection screen are always those with the lowest Dragon Level and Enchantment Level. As these are the only two factors taken into consideration when an eligible Dragon is decided by the game, whenever two or more duplicates have the exact same levels, the displayed one will always be given at random. Once a Dragon is chosen, the Trainer will be prompted to confirm the choice through the Yes! Ascend dragon! button or to infirm it through the No, I want to keep it! button.
If the choice is confirmed, the ascension process will instantly begin and will last 24 hours and can be sped up through the use of Gems. Since ascending a Dragon is an irreversible process, the same as selling, the ascended Dragon will be permanently removed from the Trainer's game.
Once a Dragon has been ascended, the icon will appear above the Enchantment Altar. Selecting the Altar will then give the Trainer a chest containing between one and three material cards. In the case of Divine and Ancient Dragons, the Trainer will receive a separate , respectively material card for the Divine Element and Ancient Element, respectively, right after the material cards for the secondary Elements have been claimed.
The number of material cards and the quality and amount of the Enchantment Materials depend only on the rarity of the Dragon and whether it is marked with in the selection screen or not. No other factors are taken into consideration. The rarer a Dragon is, the higher the chance that more and higher-quality materials will be given.
Dragons that are not full set will only give one material card for one of their Elements chosen at random while full set Dragons give material cards for all of their Elements. In the vast majority of cases, only Limited-Time Dragons bear the mark. Dragons with inactive Elements need not have their secondary Elements awoken in order for them to count for ascending.
Selecting the Enchantment Altar during ascension will bring up the option which displays the amount of Gems needed to skip the remaining ascension time. Selecting the option will bring up a window where the Trainer can see the time left until the Dragon can be ascended, and the SKIP ALL button. Pressing this button will speed up the remaining time, allowing the Dragon to be ascended.
The Gem cost for skipping the ascension timer is calculated based upon the following formula:
(TimeInSeconds ^ 0.45) * 0.15 and the final result is rounded up by 1 if it is between the 1-10 range, and by 5 if it is between the 10-100 range. For example, the cost to skip the initial ascension time (1 day) is: (86400 ^ 0.45) * 0.15 = 24.9 - rounding by 5 applies, thus the cost to skip the timer is 25 Gems.