|• Crystal generation|
• Magic resistance +20%
• Counts as dragon
"Made entirely from red crystal and brought to life through magical means, the Crystal Dragon is literally semitransparent, lit from the center by its magical heart. Used frequently as a training tool for young dragon slayers, many wizards also create these creatures for the crystal they shed." AB manual
Crystal generation special ability
Crystal Dragons have vaguely phrased special ability called crystal generation. It produces three crystals (3x ) at the beginning of each week if the player has at least one crystal dragon in any of his armies. The effect is not cumulative, which means that several crystal dragon stacks in a hero's army or several crystal dragon stacks in different heroes' armies does not produce more than the three crystals.
Crystal Dragons were added in Armageddon's Blade so there are no Crystal Dragons or Crystal Caverns in Restoration of Erathia. They also appear at the end of the Crystal Dragons scenario from the Dragon Slayer campaign in Armageddon's Blade.
Tactics and info
Crystal Dragons have the second highest defense and health value, right behind the Azure Dragon. In all stages of the game, these dragons are terrible foes, fast and hard to get rid of.
Just like toughness, they have the second highest attack and damage value in the whole game. With their fast speed and excellent stats, they are the perfect troop to kill and block the enemy archers and withstand the blows of the enemy.
Efficiency and cost
There aren't that many strategies involving them, since they are a pretty simple, but effective creature. Fast speed allows them to reach any unit on the battlefield, and high stats make them effective tanks and attackers at the same time. However, unlike most other dragons, Crystal Dragons do not fly so they will have to navigate around obstacles (their high speed helps) and will be blocked by castle walls and moats.
Even though in the game files themselves the Crystal Dragon and other neutral dragons are considered to be level 7, the official editor shows they are level 10 (8 for Faerie Dragon). This is either due to code limitations and impossibility of creating a unit with tier higher than 7, either because the developers didn't have time, motivation or reason to add a new creature level in the game code and invest time in that, just telling us they are level 10, respectively 8. As such, even now their levels are still being debated.
They are also the second strongest creature in the game in raw stats, the first being the Azure Dragon. Crystal Dragons can also be resurrected, probably due to their magical heart, even though they are considered to be golems.