Ninja?

Inexpensive Cards to Buy

Katsu is built (like many FaB decks) on a foundation of cheap commons and rares. The following are must-have cards for the way Katsu is currently built (in Q2 2024), but has been relativley stable for years. Picking up these cards will put you in a good place moving forwards, and likely also for Zen's release.

Card Description
Heartened Crossstrap is a cheap chest that has become standard in the Katsu CC deck due to its ability to enable a huge turn. Free Surging Strike, it turns out, is really good.
Surging Strike in both Red and Yellow are critical to the Katsu combo-lines seen in pretty much every classic constructed deck. It's the starter for both the Lord of Wind and Bonds of Ancestry lines, and is pretty much required. It's also a very inexpensive card, so it's not difficult to pick up a playset!
Be Like Water is another 3 copies of almost Surging Strike and demands blocks, so it's essentially required. It's also a 0 cost for Katsu. It's also, like, 5 cents.
Descendent Gustwave is a staple in the deck as well, also in red and yellow. The use of harmonized kodachi's prevent the usefulness of including blues. Many decks only run 1 or 2 yellows, but as a common, I'd reccomend just picking up 3 copies.
Whelming Gustwave is a great follow-up to Surging Strike, across all colors. A lot of decks only run Red and Blue. The 4 power breakpoint is very powerful, and the 0-cost blue works great with Harmonized Kodachi.
Bonds of Ancestry has become central to the way the modern Katsu deck operates. Using the Katsu search, Mask of the Pouncing Lynx, and Breeze Rider Boots, you can stack several Bonds of Ancestry with gustwaves inbetween to deal massive amounts of damage, and potentially end with a must-block Dishonor. Decks generally only run 1 blue Bonds, as it's not a 0-cost to activate kodachi, and the number of yellows you play varies. I'd get 3, just in case.
Breaking Scales is not only cheap, it's also best in slot for Katsu. It forces the opponent to overblock the entire game, until they don't, and then you kill them.
Flik Flac is an excellent defense reaction, that works well with all the blue combo cards we're already running. It's a sideboard card for certain matchups, that is especially good in more controlling decklists.
Fluster Fist red does good damage with the 4 power breakpoint, and the blue 3-block 0-cost is good on it's own. Coupled with the Bonds of Ancestry synergy, and 3x of red and blue become staples.
Most decks just run the red Hundred Winds, which is a powerful, potentially scaling, go again attack. It's held back by only having 2 block, but is great at buffing itself and Winds of Eternity. I think the others might be played more in the future, so it might be worth getting the whole set if you're getting into Ninja.
Spinning Wheel Kick is good (and bad) for the same reasons hundred winds is, but with a bit of every power in the attack column. 3 red copies is included in a large percentage of lists.
Tide Flippers are a solid pair of arcane barrier boots: they aren't great, but they have at least some up-side if you do want to bring AB!

You can buy all the cards above using this link!

Mid-Priced Class Majestics

Katsu is unique in that a lot of his cards are good because they combo directly with other cards. These Majestics are the REASON you want to be playing Katsu as they are the payoff for the lower lines. There are no cards in any deck that are a "must buy," but some of these ninja cards are highly impactful to the way the deck operates. This guide is being written in May of 2024, and since prices change I won't be calling out specific values for these cards. But, if history is any indication, I'd expect these to vary in price between a couple bucks, to ~10 at the high-end. Before each card I've rated how important a purchase is on a scale of 1-10.

Card Description
[10/10] The ninja class has become centered around this card. The deck revolves around stocking the graveyard with gustwaves and bonds. Then, when the hand is right, you attack with Surging Strike. On hit, you search your deck for a gustwave or a bonds with Katsu's ability, crack this mask for the blue bonds of ancestry, then when you attack with bonds, you grab another gustwave that has go-again due to Breeze Rider Boots to activate the second Bonds. From there, you can attack with a Dishonor to force more blocks or a red Fluster Fist in a pinch. The deck presents lots of damage over the course of one, very high powered turn.
[10/10] Breeze Rider Boots enable this combo by giving your free Whelming Gustwaves go again during the combo turn, in addition to having battleworn 1 for extra value.
[9/10] This card does pretty much exactly what Katsu wants to be doing. It's a 0-cost so it turns on Katsu's hero ability, it has combo so you can tutor it, it's blue and blocks for 3 so it is always useful, and just the threat of activating that on-hit forces the opponent to play very very carefully. You'll want a full playset.
[9/10] In Katsu, you need your attacks to hit. Ancestral Empowerment is critical to that gameplan, on top of blocking for 3, drawing cards, and costing 0. A playset is played in most modern Katsu decks to threaten on-hits.
[9/10] You know the drill. 0-cost, blue, 3-block. And it combos with Hundred Winds. What's not to like?
[6/10] Ancestral Harmony checks a lot of the boxes: blue, 3-block, 0-cost. The actual effect is okay, it's a mini Art of War, sometimes (more on AoW later). Modern Katsu decks only run a couple of these, because of the aforementioned Generic, but if that card is outside of your budget, running a full playset of this is an okay replacement. Picking up 3 isn't a horrible idea, but if budget is a consideration you don't lose much, if anything, only picking up a couple copies.
[6/10] Lord of Wind used to be an auto-include in all Katsu decks. These days, some decks are a little more Bonds-combo focused, trying at all costs to get off one CRAZY turn. If you're going to be skimping on some of the really expensive cards in the deck, the line is still very strong and requires 1-2 copies of Mugenshi: Release. It's worth picking up some copies.
[6/10] You can't Lord of Wind without, well, Lord of Wind. I love this card, I'd be putting it in my ninja deck almost every time. Your perference might lie elsewhere. It's a suprisingly good budget option though, and if you're not going to run Art of War, you're going to want 3 of these. If you do run AoW, you probably still want 3.
[3/10] Blazen Yoroi is a pretty good sideboard card in the mirror and into go-wide matchups. It's not the best meta for it, but if the card is cheap grabbing a copy isn't the worst idea.
[2/10] Find Center is a card that combos with Flick Flak and is generally used in more midrangey Katsu decks. It's not played in most standard list at this point in time though. That said, if you're not going to be purchasing Warmonger's Diplomacy, it's a great blue that fills out the deck if you need more cards.

You can buy all the cards above using this link!

Expensive Legendaries + Generics

There are only a couple very expensive cards played in a number of current Katsu decks. Katsu has moved away from some of the very expensive cards that used to be required. However, midrange katsu decks still exist, and if you're interested in Mask of Momentum they continue to be required.

Card Description
[10/10] Art of War is a card that if you are playing full-combo Katsu, you almost certainly want to purchase. It can push through an unexpected on-hit, draw you out of awkward hands, and generates TONS of value over the massive number of chain links the deck generates.
[7/10] Tenacity has become a popular card as the game has shifted to more defensive decks, and the increasing strength of equipment. I'd reccomend picking up a couple copies, as many decks run 1 or 2.
[5/10] Sink Below is a solid card across a lot of decks, and Katsu is no exception. If you've made some budgetary cuts, they are good to fill out your sideboard. Reinforce the Line is another good potential option.
[3/10] I personally love Mask of Momentum. However, the deck has moved far in the direction of Mask of the Pouncing Lynx. That said, there's a slower, more defensive version of the deck that runs more blues, less Bonds of Ancestry, and Snapdragon Scalers. This card was also useful in the Dromai matchup, which is no longer required. This card is much cheaper than previously as of May 2024, so if you have interest in the deck I would suggest picking one up!
[3/10] If you are playing this slower, more defensive style, you'll want to run Fyendal's Spring Tunic instead of Cross Strap. Tunic is an incredible card, and a great generic to pick up. With that said, if you plan to play the full combo version and aren't just looking to pick up staples, this is an equipment you can skip.