Castlevania: Dawn of Sorrow

Castlevania: Dawn of Sorrow (frequently abbreviated DoS) is a video game for the Nintendo DS developed and published by Konami. The game is a direct sequel to Castlevania: Aria of Sorrow, and features Soma Cruz as its protagonist. Other characters from Aria of Sorrow also return, including Soma's girlfriend Mina Hakuba, Genya Arikado, Julius Belmont, and Yoko Belnades. The game takes place one year after the events of Aria of Sorrow and details Soma's exploration of the castle of an enigmatic cult which seeks to destroy him.

Basics
Note: The, , , , , and buttons are customizable from the in-game menu screen.
 * : Move Soma; select menu items
 * : Perform a special attack with the equipped weapon (this consumes MP)
 * : Jump
 * : Switch between the A and B equipment sets (only after acquiring the Doppelganger soul)
 * : Perform a normal attack with the equipped weapon
 * : Activate the equipped guardian soul
 * : Dash backwards
 * + : Activate the equipped bullet soul
 * + : Perform a slide attack; jump down to lower levels when on narrow platforms
 * : Toggle the top-screen display between Map View and Status Window sub-screens
 * : Pause; display status/settings menu
 * + +  + : Perform a soft reset and return to the game's title screen

The action in Dawn of Sorrow takes place on the bottom, touch-sensitive screen. During gameplay, the stylus is used to break certain "ice" blocks, navigate menus, draw Magic Seals, or control certain familiars.

The top screen operates in two modes, which can be switched by pressing Select. The main mode displays Soma's status and currently equipped souls. It also provides information about Soma's most recently encountered enemy, including its name, information about its resistances and weaknesses, and the number of souls of that enemy currently in Soma's possession.

The second mode displays a map of the castle. Your current position is indicated by a pulsating circle. Save rooms are indicated by red squares, and teleport rooms are indicated by blue squares. Green partitions represent doors. Explored areas appear tan, while unexplored areas for which you have a map are indicated in dark gray.

Advanced moves

 * Jump Kick: Requires the Malphas soul. Perform a double jump and press while holding down or diagonally-down on the Dpad. If you hit an enemy or breakable object you can repeat the jump kick.
 * Charged Jump Kick: Requires the Malphas and Medusa Head souls. Hit as soon as you perform a jump kick and hold it. When you release it you will continue the jump kick, but it will do more damage than usual. Hold for as long as necessary, and have fun!

Soul-Specific tips

 * Succubus: The Succubus soul deals more damage, and therefore restores more health, with higher INT stats. It also steals hit points from inanimate objects! For instance you can "bite" breakable lamps, pots, statues, and chairs. So for maximum health recovery equip INT-boosting items and souls, and go through rooms full of breakable items.

Easy leveling up
These are some good suggestion on easy leveling up:

Wizardy Lab: Merman room

 * Get the Persephone vacuum soul, and level up until you are able to use it to kill a Merman (45 hp) in one hit. Next, go to the basement of the Wizardry Lab, to the room below the room with the Ghosts and invisible walls. There you will find 16 Mermen in a line; simply go in and out of the room, using Persephone's vacuum to continually kill the Mermen and gain an exorbitant amount of experience points.
 * Another good strategy is to equip the Black Panther and Mothman souls, the Shaman Ring, and Nunchakus (acquired from Boss Rush Mode) and simply zip back and forth--each pass should take about 4 seconds. In this case, the Nunchakus are better than Valmanway because they can be used continuously. With the Shaman Ring and Mothman, you will gain 1488 exp per run; without, only 960 exp.
 * Alternatively, still with Black Panther soul equipped, use Imp soul, and wear items that enchances your INT. Activate Imp, which will suddenly set Merman's HP into just 12, then just zip through them. Oh, and of course, Shaman Ring is ever so recommended.

Iron Golem

 * In the room left of the Ghost room in the basement of the Wizardry Lab. There, use the Bat Company soul to fly over the Iron Golem, then use the Buer soul (level 9), Dead Pirate soul and Valmanway (Nunchakus and Kaiser Knuckle also work well, except that their range is short, thus risky) to quickly destroy the Iron Golem and gain 2000 exp.
 * If you don't like the large room in the Wizardry lab, you can also try the small one on the top-left-most room top-most tower in the Demon Guest House. In this case however, you cannot use Bat Company soul at all.

Boss Rush Mode rewards
Unlock Boss Rush Mode by completing the game and getting the best ending. Beat Boss Rush Mode under the stated time to receive the corresponding reward.

The three money doors
In the castle, three gold doors contain rare items. To unlock a door, the last three digits of your gold must match exactly the three digits on the lock.