Balance. This combination is what I'd call an improvement on MSF-H Wyvang Wyvang BD145RSF. Super Heavy, tank-ish weapon, used to KO anything that isn't on a hardcore Defense setup, greet Attack types with a collision so chaotic they don't have a chance to fight back, and out-bulk and out-bash opposing Defense types into submission.
I got butterflies in my stomach writing that paragraph. This is my dream combo.
Now, there's a weird story behind this. I actually first tested this combination back in
July of 2013 when I was writing the Wyvang Wyvang BD145RSF thread. For some reason, I just couldn't get any aggression out of it. I couldn't get it to KO Duo Stamina customs more consistently than, like, 40% (give or take a few - this was a year ago), but it always stuck in the back of my mind, because every time I played/did testing with the RSF variant, I thought
"Wow, that really should have worked better than RSF. I wonder why that was..."
Well, I finally decided to just re-test it and get that lingering voice out of my brain, and... well, as non-thorough as I was back then, I'm positive I must've been using an unevenly-worn RDF, or forgetting to clean it between rounds or something (which is important - RDF builds up residue fast, and it's aggression really declines if you don't clean it every round), because when I tried it this second time, it was actually being
more aggressive than my RSF, and producing a far higher KO rate; up to
70% against a top-tier Defense custom!
Anywho, I found that, as long as your RDF is wearing evenly and it's still flat on the bottom, and you remember to clean it well between rounds, you can pretty easily get more aggression out of it than you could out of RSF.
This comes with an added benefit. If we can get enough aggression out of it by using a clean, flat Rubber Defense Flat Bottom, we can also get added recoil reduction, and vastly superior performance against opposite-spin opponents, two of the original custom's most exploitable weaknesses. BD145RDF is one of the most Precession - loaded setups in the game, and by using it, we can easily OS many different Dragooon customs that MSF-H Wyvang Wyvang BD145RSF can't. Along with this, RDF's traction and Defensive ability helps a lot with Wyvang's recoil, and allows for safer KOs against Stamina/Defense customs, and higher overall win rates against Attack types.
One disadvantage this Bottom has relative to RSF, is Stamina. It just isn't able to out-spin the things RSF is able to out-spin; right?
Wrong! Wyvang is an extremely aggressive Wheel, and whenever it collides with another Beyblade, the opposing forces working against each other are huge, which causes quick, severe bursts of spin loss for both Beyblades.
When out-spins are being caused by chaotic collisions, more stable Bottoms tend to resist significant spin loss more effectively, even if their pure endurance isn't top-notch. RDF is far more stable than RSF, and because any spin loss this custom suffers or inflicts is so chaotic, RDF's stability makes up almost entirely for its low endurance.
By using such a bulky setup (relatively low center of gravity, only 1.4 grams lighter than the heaviest buildable Beyblade combination and 3-4 grams heavier than the heaviest Defense custom on the tier list), and topping it off with the ever-solid RDF, Wyvang's aggression will actually allow this custom to out-bulk other BD145 Defense customs and bash them into an OS pretty reliably.
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It really does seem like Wyvang and RDF were made for each other. This custom beats so many different things, it's honestly pretty tough to win against, even when you know it's coming. It's just such a hulking, explosive, sort of tank-ish mass, making contact without losing is difficult. I'd confidently call this one of the most versatile Standard Format combinations I've ever seen (one of the easiest to use, too).
And to think I just skipped right over it because I was using the wrong RDF. :\
Let this be a lesson to you, guys. If you get terrible results with a combination that seems logically like it should be working really well, always check each individual part and go back and test it again later. You might miss something awesome.