Temp info from Dukemon:
KishiRyuuOh (Red T-Rex), Triken (Blue Triceratops) and Ankyloze (Pink Ankylosaurus), TigerLance (Green Sabertooth) MilNeedle (Black Stegosaur?)
The RyuuSouls seem to be "knight spirits". They are definitely like RangerKeys, and install in the mecha.
-Triceratops should be "TriKen" as it's a sword. Still not sure what kind of weapon Akyloze is.
-The three initial mechs combine to form KishiRyuuOh 3 Knights. It's one part gattai, and one part armament.
-TigerLance combines with 3 Knights to form KishiRyuuOh TigerLance. This 4-combo seems to actually have a new head.
-MilNeedle (seemingly a stegosaur) combines with 3 Knights to form KishiRyuuOh MilNeedle.
-The Henshin Sound for the RyuusouChanger is "Ryuusou Cool!" (RyuusouChanger comes with another RedRyuuSoul.
-The RyuuSouKen comes with another Soul.
-Can't make out the names of the other Souls, but like the ZyuDenChi and KyuTama, they definitely give mini power-boosts/attacks. (One says MukiMuki, like Muscular.)
-The RyuuSouBuckle comes with another Soul, and can store 3 souls, as well as holding the RyuuSouKen