Nov/Dec 2025 UNION ARENA Rare Battle Guide: Kaiju No. 8, Rurouni Kenshin, Yu Yu Hakusho, Hunter x Hunter
Ready for another round of Rare Battles? We’ve had some insanely fun Rare Battles this year that have spanned the scope of some of the most popular and recognizeable anime in history. To close the year out we have a solid lineup of titles to choose from: Kaiju No. 8, Rurouni Kenshin, Yu Yu Hakusho, and Hunter x Hunter.
Below, we’ll be taking a high level look at each of these Rare Battle formats, the prizes you can take away from them, and some strategies and deck ideas to help you triumph at your event.
#1 Kaiju No. 8
My guess is that Kaiju No. 8 will be the most popular Rare Battle. It’s a very recent anime with a lot of hype around it, and from what I’ve seen via web trends it’s one of the more popular UNION ARENA sets to date. However, it’s also going to be a relatively unique format given the smaller nature of the Kaiju No. 8 set. With only two energy colors to choose from and four main decks, there may not be as much variety at your Rare Battle as you are used to.
However, never count the endless creativity of UNION ARENA players to come up with something out of the box. With that being said, here are the decks you should be looking out for:
Mina/Reno is Kaiju No. 8’s strongest deck
1st place deck by Joseph Writer Anderson
The top meta deck from Kaiju No. 8 is Mina/Reno, meaning you are most likely to run into this powerful deck combo. However, there are admittedly vastly different ways to build this deck, so the exact deck build you run into is likely to differ from event to event. Some players will lean more heavily into Reno, some will go for more of a pure Mina build and leverage the exemplary Soshiro. Regardless of how this deck is built, however, five-cost Mina remains its biggest threat, capable of resting and freezing opposing characters.
Kikoru is the dark horse of the Rare Battle format
While Mina/Reno is arguably the strongest Kaiju No. 8 all around, don’t underestimate Kikoru! This deck forsakes late game strategy in favor of early game aggression, looking to dominate your opponent before they set up their strongest plays. It’s a bold strategy that could very well pay off in a meta where most players haven’t dealt with a deck that moves this quickly before.
#2 Rurouni Kenshin
Rurouni Kenshin should also be a popular Rare Battle format, although it’s decks are more proven in the English version of the meta. While players will undoubtedly play a wide range of Rurouni Kenshin decks given how strong many are, ultimately the strongest matchup will come down to Red Kenshin vs Purple Saito. Both are strong decks that counterbalance one another, and I’m sharing two optimized builds below: one from a second place deck at a case tournament by Vexsten and the other by Regional Champion, Mylo.
Additionally, the Rurouni Kenshin Rare Battle has the distinction of offering the most meta-releavant UNION RARE Winner card, meaning many hyper competitive players who like to run Red Kenshin will be looking to bag that card in order to bling out their deck.
#3 Yu Yu Hakusho
If I had to pick one of the December/November 2025 Rare Battles to be most diverse in terms of its play share, I would bet on Yu Yu Hakusho. This set boasts a lot of strong decks that hover around similar power levels, making it ideal for players who want to try something unique.
That being said, the strongest deck to watch out for is the Toguro Brothers.
You can think of Toguro as a slightly less effective Green Lancelot. It hits hard, has plenty of removal, and offers some decent consistency as well. While there are many strong Yu Yu Hakusho decks that can certainly compete with it, my money is on Toguro for being the standout deck in the Rare Battle format.
#4 Hunter x Hunter
Finally, there’s Hunter x Hunter. Despite being one of the weakest sets overall, Hunter x Hunter has a loyal fan base, and the Rare Battle events for this one should be popular. While there are plenty of strong Hunter x Hunter decks players will undoubtedly get creative with, my money is still on ye old faithful Kurapika.
While this deck fails to compete exceptionally well into the current UNION ARENA English meta, I could see it being quite dominate in a Rare Battle format. Kurapika’s combo of Snipe/Impact will be absolutely deadly within the confines of its own anime set. And while other, contemporary decks do what he does better, nothing in Hunter x Hunter can compete – even with Vol 2 that only makes Kurapika stronger.
What deck are you planning to bring to your UNION ARENA Rare Battle? Share your thoughts below or join the Discord and share your deck via the UNION ARENA decks channel!
