@BeLKastel what is your opinion on Yellow so far? I'm most interested in its DP lowering
Pre-BT2 Yellow was the weakest colour imo, the game plan that was being pushed forward was one that focused on increasing your security to well above the normal 5. They got buffs from fulfilling those conditions but it was more a strategy of "not losing" than "winning". That said they still had their DP lowering strategy, but it was too slow to pull off. Other decks had more consistent destruction methods that didn't need as much an effort as Yellow did to reduce DPs to 0. With BT2 the recover strategy is actually a lot better because it can work in tandem with DP reduction. Cards like Hikari give you a huge bonus for keeping yourself at 3, Angewomon from the starter deck also strives to keep you at 3, same with Plotmon from BT2. Hikari in particular works very well with Starter Deck Takeru, both stack with other copies of themselves and they become this metaphorical wall that keeps your opponent from attacking. They will most likely lose resources trying to get over your Takeru enhanced things, and if they don't finish you off, Hikari will most likely give you a memory edge, allowing you to recover the security you lost.
As for DP reduction, BT2 didn't focus too much on it aside from the ShineGreymon strategy, that I'll be getting into in a bit, but BT2 did bring Eden's Javelin which is a great card, especially if hit in security. It replaces itself when used from the hand, and has the potential to pop even lv6s if you have enough cards in hand, but for that you need a dedicated build.
Now for the ShineGreymon builds. These tend to be more traditional evolution-line based builds, with the end game being ShineGreymon of course. His setbacks are needing a lot of Tamer investment and unfortunately you'll need to play a few copies of BT1 Takeru, on the other hand, RizeGreymon allows you to play it for free on evolution so it's not all bad, and for all the non-things he does, getting you to 3 memory allows for Hikari to stack from 3, meaning you'll always have resources for plays.
Now a cute thing ShineGreymon can do is combo with Labramon, note that to date this combo only works with these two cards, Mistymon, will not produce the same effect. Lets say you have 5 Yellow Tamer cards out and you evolve into ShineGreymon and Labramon was the lv3 used in the evolution line. ShineGreymon will activate and rest all 5 Tamers allowing you to activate the -4k DP effect 5 times. For the sake of argument lets say you use each of those effects on a different digimon and they all get destroyed. Because the destruction happened due to a different effect, Labramon will trigger upon each destruction letting you draw 5 new cards, which is crazy advantage. The reason why it doesn't work with Mistymon is because despite possibly giving you two destructions, they come from the same effect, and ShineGreymon specifically states that each 4kDP reduction is a new effect.
That is a shortened version of feedback on Yellow as a pure colour deck. I actually recommend playing Wizarmon even in pure Yellow decks, he is cost 4 and comes with the Drag-Down effect when there is a Yellow in play, furthermore he draws you a card when he dies. But that brings me to the mix decks. Yellow is a mid-tier deck imo as a pure build, I think Yellow is much better as a support colour in other colours. I myself play a Yellow/Purple build as I've said before, but there are also Blue/Yellow builds that seem to be popular, and were popular before BT2. However I haven't seen any Blue/Yellow deck in action.
