The Charm of Arcana increases the percentage of energy.
The in-game description in 1.0 and 1.0.1 said that arcana increased both energy and health, though the only impact in the game was to increase energy. The description has been fixed in Update 1.1.0 and the effect to energy was also double in that update.
|1||+2% to Energy||312||0:02:04||125||0:04:59|
|2||+4% to Energy||781||0:15:01||312||0:12:38|
|3||+6% to Energy||1,953||0:47:32||781||0:21:50|
|4||+8% to Energy||4,882||1:47:39||1,953||0:32:02|
|5||+10% to Energy||12,207||3:22:53||4,882||0:43:11|
|6||+12% to Energy||30,517||5:40:32||12,207||0:55:10|
|7||+14% to Energy||76,293||8:47:34||30,517||1:07:47|
|8||+16% to Energy||190,734||12:50:52||76,293||1:21:07|
|9||+18% to Energy||476,837||17:57:06||190,734||1:34:59|
|10||+20% to Energy||N/A||N/A||476,837||1:49:23|