|This article is about a/an villain in Kamen Rider W.|
Taizo Kaga (加賀 泰造 Kaga Taizō) is the Money Gaia Memory user.
He is a life-long gambler who is able to use others' tells to win. He is also the owner of the secret Million Colosseo (ミリオンコロッセオ Mirion Korosseo) casino, using his powers as the Money Dopant to enforce payment of debts. By tricking debtors into having them bet their life force in a game of chance, many debtors lose their life. Shotaro and Philip are able to beat Kaga out of all of his Life Coins in a winner takes all game of old maid. After the Money Dopant is defeated and the Money Memory broken by means of the Metal Branding Maximum Drive, the Life Coins are unsealed and everyone is returned to normal.
- Main article: Money Dopant
As Money Dopant (マネー・ドーパント Manē Dōpanto), he uses his powers to seal their life force into pseudo-memories called Life Coins (ライフコイン Raifu Koin) after they lose. As he holds the Life Coins in his Dopant body, his destruction would cause all of the people to die.