This set also contains a complete Bulbasaur evolution line with Venusaur SAR
They also have a Trigger Effect upon Special Summon, like adding more Spright Cards from the Deck to hand, or negating an opponent's card
For instance, if Lorehold's effect was a loot (drawing then discarding) instead of a rummage, the combo wouldn't be nearly so clean (it would still be powerful, just a little easier for your opponents to disrupt)
The idea is pretty simple: Banette or Dhelmise are your best attackers in normal situations and if you see an opening, you can simply change your opportunity to spreading damage counters with Sinistcha or Sabeleye
Green is not traditionally an artifact-supporting color, but there are more than enough Artifacts in Blue for the Sixth Doctor to boost alone, making him an incredibly potent new commander
And it also draws you cards