So the core idea of DDT is simple; you want to summon Diamond Dude as
soon and much as possible. To enable this, we run a few cards to set him
up. We combine his ability with a lot of power spells, mostly fusion spells
to ensure his effect goes off hard. Most of the spells however can also
just regularly be used, like Red-Eyes Fusion or Neos Fusion. We run a few
garnets in the deck to facilitate these spells, but a lot of them have
other uses like being targets for Dark Calling.
On top of that, the Predaplant link also gives us consisten access to the
various fusion spells to make for a powerful fusion powerhouse.