"The Ruins Of Delgantua" level:
To unlock "The Ruins Of Delgantua" level, beat all levels without any crystals.
The bonus money you are awarded is based on the amount of gold you save and crystals.
Champion Defender - Clear all 12 maps.
Crystal Hoarder - Clear a single map without losing any crystals.
Expert Defender - Clear all the waves on any single map.
Novice Defender - Clear wave 10 on any single map.
Seasoned Defender - Clear wave 20 on any single map.
W1 Defender - Clear all the maps in W1.
W2 Defender - Clear all the maps in W2.
W3 Defender - Clear all the maps in W3.
Four-Star Strategist - Accumulate a total score of 100,000 points.
Overachiever - Clear a map with more than 10,000 points.
Veteran Strategist - Accumulate a total score of 50,000 points.
Good Samaritan - Clear a map without deploying a thief or losing a single crystal.