I realised the reason why Beast Box is not that popular in the current competitive meta is because people were mostly trying to build it with 1 basic energy and Naga+the UB-GX that matches the chosen basic energy type. However, due to the fact that Naga is a single energy attacker and that some of the non-GX UBs can also contribute for a single energy I think Beast Box should be built with a bit more freedom and not the "min-maxing" mindset that the usual competitive deck should follow. When building Beast Box, you also have to take into consideration which UBs have the most firepower while also being a partner that make up for Naga's bad qualities. For example, right now Buzz is still the best UB, but pairing it with Naga is not that good of an idea, as both are weak to psychic in a meta where Dawn Wings suddenly went "from zero to hero". Dusk Mane is an ok partner, but you can't just put in a 4-3 Naga line and 3-1 Dusk Mane-GX/baby split and call it a day, as Dusk Mane's attack costs way too much and also requires you to discard 3 energy, and with the condition of Beast Ring, it is impossible to consistently chain KOs with Dusk Mane with just Beast Ring as energy acceleration. So, the list I propose is the following: Spoiler: List 1 Buzzwole 2 Dusk Mane Necrozma PR-SM 1 Dusk Mane Necrozma-GX 1 Kartana-GX 1 Dawn Wings Necrozma-GX 4 Poipole 3 Naganadel-GX 1 Tapu Lele-GX 4 Ultra Ball 3 N 2 Super Rod 3 Professor Sycamore 4 Cynthia 4 Weakness Policy 3 Guzma 4 Float Stone 4 Ultra Space 3 Beast Ring 1 Beast Energy 3 Fighting Energy 8 Metal Energy I actually don't play a Lele in my current list and put in 1 Ultra Recon Squad instead, but I figured I'd already get roasted for including Weakness Policy - with Ultra Recon being on the list too it would have been too much The reason I personally don't want to play a Lele is simple - I don't want to bench anything else other than UBs. I figured that, in order to avoid bricking on turn 1, two Leles are better anyway, which is just too much for this deck and instead I tried to put in as many draw supporters as possible. But of course you can always play the 1 Lele. Weakness Policy: Naga needs to be the main attacker, period. Otherwise Beast Box will not work as you can only rely on Beast Ring to accelerate energy. You will most likely only use Dusk Mane-GX once (or twice if you're lucky) to take a KO. However, most of the time Naga can't take any OHKOes by itself (only exception is Choice Band+Beast Energy on less than 190 HP GXes) and Dawn Wings with Malamar demolishes it with little to no effort. In order to try and mitigate this problem I decided to include Weakness Policy instead of Choice Band, since you will be relying on baby Dusk Mane to fix the numbers for Naga anyway and Dusk Mane-GX doesn't need Choice Band most of the time to get a KO. Why not play Buzzwole and only basic fighting energy if I'm already playing Weakness Policy anyway? Because there's no room for Elixirs, and without Diancie, Choice Band and Strong Energy, Buzzwole suddenly isn't the absolute monster it usually is. Baby Buzz is too good to pass up, that's why I made a 8 metal/3 fighting energy split, but I guess you can also go 9/2. It OHKOes Zoroark and safeguarders and in every other case 120 for 1 basic energy from a 130 HP 1 prize attacker is never a bad thing. When the new Celesteela gets released I will definitely need to find room for 1 copy. (But not more as it is also a very bad starter and I want to decrease my chances of starting with anything else other than Poipole or baby Dusk Mane. Plus its attack cost is way too high if the condition isn't met.) 2 Super Rods because you need to be able to recover after a Parallel City or two. I think 4 copies of Ultra Space are needed, as you only have 4 Ultra Balls, can't afford to use Brigette and you can only draw cards with supporters. Therefore, being able to search out 1-2 (Ultra Ball+Space) UB every turn is very important. You also need to counter Parallel City. As long as Float Stone is in the format, I think Dawn Wings is a no-brainer for any Beast Box build. Kartana's use is obvious, but if you were able to get by without having to use Dusk Mane for the GX attack, you can also use Blade-GX to close games, as you're mainly playing metal energy. Thanks a lot for reading and feel free to share your thoughts about the idea of the list!