Secrets

In Tenchu: Return from Darkness you can unlock extras depending on your progress in story mode and the rankings you get. In 2 missions additional items are hidden (Stone of Power, Fugaku and Dokuto). All secrets can also be unlocked by using cheats.

Tesshu:
Beat the game with Rikimaru and Ayame. Tesshu is now selectable at the character selection screen.

Through the Portal:
Beat the game with Rikimaru, Ayame and Tesshu to unlock Rikimaru’s secret mission "Through the Portal" on difficulty normal or hard.

Stone of Power:
The "Stone of Power" is hidden on the floor beyond Dr.Kimaira in Amagai castle at the exact same location for both characters (Ayame and Rikimaru). Check out the secret doors on that floor. One leads into a room which has a ceiling dropping down on you. Huury and grab the Stone of Power located in the center of this room (red box).

Dokuto:
Ayame’s poisoned swords are hidden in the mission Retrieve the Jewel of Heaven within a room hidden in a large L-shaped pit.

Fugaku:
Rikimaru’s additional sword is hidden in the mission Infiltrate the Buddha Temple at the end of a large pit.

Semimaru:
Get Grand Master ranking on all missions with Rikimaru (one layout is enough). Semimaru will then be playable in Multiplayer Versus Mode.

Ninja Dog:
Get Grand Master ranking on all missions with Ayame (one layout is enough). The Ninja Dog will then be playable in Multiplayer Versus Mode.

Rikimaru’s 2 Endings:
Rikimaru has 2 different endings. The ending depends on the choice you make at the beginning of mission 6 "Retrieve the Steel for Ressai". You don’t need to replay the whole game to get the alternative ending. Simply go back to mission 6 and take the other choice, save the game after beating the mission and proceed to mission 9 "Assassinate the Evil Tenrai". The videos at the end of mission 9 and 10 will be different now.

Ayame’s 2 Endings:
Ayame has 2 different endings. The ending depends on the choice you make at the end of mission 6 "Escape from Castle Amagai". You don’t need to replay the whole game to get the alternative ending. Simply go back to mission 6 and take the other choice, save the game after beating the mission and proceed to mission 9 "Assassinate the Evil Tenrai". The videos at the end of mission 9 and 10 will be different now.

B-Side:
Get on all of Rikimaru’s and Ayame’s missions at least the rank Expert Ninja and on all of Tesshu’s missions at least the rank Professional. Then you can choose under "Option – Sound – Languages" a 3rd "language" (next to Japanese and English).
You will get the exact same cutscenes in the game but with different English voice overs/dialogues. This will only work in the North American and UK version of Tenchu: Return from Darkness.

Bamboo Forest Hot Springs:
Take a bath in the hot springs (crouch) to slowly regain your stamina.