Elebits: The Adventures of Kai & Zero [NDS]

Big Red Omega
Select "Extras" at the main menu, then "Download Additional Omegas", then "Download Data". Then, press B, Y, Up, L, Right, R, Down, Left, X, A. When Big Red is activated, Kai's capture gun meter will have double the time to capture Elebits that he has stunned.

Bonus Omegas
Complete the indicated task to unlock the corresponding Omega.

Big Green Omega: Evolve all Omegas into their master forms, save on the bus, then reload the game.
Dewy Omega: Obtain all Omegas unlocked through normal methods, save on the bus, then reload the game.
Moai Omega: Load 10,000 watts into the capture gun, save on the bus, then reload the game.
Mobius Omega: Complete the game.
Night Omega: Obtain all seven diaries, then go to the Sea Temple and talk to Misha.
Penta Omega: Load 5,000 watts into the capture gun, save on the bus, then reload the game.
Takosuke Omega: Load 2,500 watts into the capture gun, save on the bus, then reload the game.
Twinbee Omega: Load 7,500 watts into the capture gun, save on the bus, then reload the game.

Night Omega diaries
The following seven diaries must be collected to unlock Night Omega.

World 1 (Elebit Forest): There is a hidden area at the top right corner of the map. Go to the bottom left corner of this hidden area to find a hidden crack with someone with the first piece of the diary. Elebits needed: Surf Omega, Ice/X Ice/Blizzard Omega, and Earth/X Earth/Land Omega.
World 2 (Elebit Mine): Deep inside the mine, at the upper left corner of the map is a hidden area. There will be a hidden crack here. Do not ride on the trail cart that appears. Follow the tracks until you see someone with the second piece of the diary. Elebits needed: Flying Omega and Earth/X Earth/Land Omega.
World 3 (Resort Island): One of the village's residents has the third piece of the diary.
World 4 (Ice World): After retrieving the X Wind Omega, use this Elebit to turn the spinning wheels with arrows pointing to a direction. It leads to a resident in the middle of the area with the diary piece.
World 5 (Ruined World): After subduing the second flowing volcano, there is a small hut on the upper right side of the map.
World 6 (Sea Temple): The east side of the maiden's shrine, at the bottom left corner of the map, is the area where the sixth piece of the diary can be found. Elebits needed: Fly Omega, Radar Omega, and Earth/X Earth/Land Omega.
World 7 (Libra of Crystal): Once the previous six pieces of the diary have been collected, the previously sealed golden door at the first floor of the upper left corner of the map will now be unlocked, allowing you to get the final piece of the diary.