Ikaruga

Accumulate Continues
For every hour of playing your amount of Continues will go up to a maximum of 9 Continues/6 hours. After 7 hours, you'll have unlimited Continues.
(Thanks to cyrin_1@hotmail.com)

Unlock Gallery 1
Play the game for 5 hours or complete the Trial Mode without continuing.
(Thanks to cyrin_1@hotmail.com)

Unlock Gallery 2
Play the game for 10 hours or complete the game on any difficulty setting.
(Thanks to cyrin_1@hotmail.com)

Unlock Game Mode Option
Play the game for 20 hours or complete the game on Normal setting without continuing.
(Thanks to cyrin_1@hotmail.com)

Unlock Sound Test
Play the game for 15 hours or complete the game on Easy setting without continuing.
(Thanks to cyrin_1@hotmail.com)