Openings: RJ's Joy

    

Continuing in discussion of specific openings, here's RJ's joy.

Like the WumbOJ, this gives a first deck T-spin single, second-deck T-spin triple, and third deck... many possibilities, but usually T-spin double. It offers another opening for dealing with "hard" first decks, where one must play the S/Z very early, with a different set of constraints than many openings. Let's take a deep dive.


1) The first deck

    

Constraints:
S < J, O < I

Here we see that we can do this opening placing both the S and Z first. Our specific constraints are S < J, O < I... and of course, we can play the mirror image with Z < L, O < I. Between S<J and Z<L, we can pretty much play this almost whenever we can drop the O before the I. I got this opening from a player named RJ, at the time #1 in Pennsylvania. From this plus the constraint, we get RJ SJOI, which makes the name RJ's Joy an easy mnemonic name.

As in the WumbOJ, we get a T-spin single for 2 lines of damage. The earliest we can do it is on the 6th piece.


2. The second deck

      

The main variant of RJ's Joy can be played in four different ways, depending on what order one gets O, S, and Z, but as you can see, they're all equivalent. We use the OSZ block to fill in the left side while we form a T-spin triple hole with IJL. Once we take the triple, we're left with a T-hole for our third deck T.

    

There's another variant where we cover our T-spin hole with the O, above, but it only works if S|Z < L. This gives us a fairly constrained third deck T-spin single + all-clear at 20, but given the constraints on both the second and third deck, it's likely not worth practicing.


The third deck and beyond

On the main variant, it's not hard to just get a third deck T-spin double. Piece 17 is the earliest we can get it:

  

Given the height of the L on the right, the earliest all-clear we can get on the main variant is at 25. It's not hard to improvise one:

    

Realistically, the only strong openings we're likely to land this against are the WumbOJ, Jail, and Long Combo--most quick T-spins and multispins will get damage past the single + triple. But it's nice to have around, just for playing against Puyo or a greedy Long Combo.


Analysis

Speed-wise, we're pretty good. We have very few constraints on our first deck and none for our second, and never need to soft-drop. We can get a T-spin triple at 14 followed by a T-spin double at 17 for some nice explosiveness; only slightly slower than the WumbOJ, but we can't get a third-deck triple.

As in the WumbOJ, our single + triple starter zones out all-clears on most openings. We lack strong all-clears ourselves, and our followups beyond the third deck aren't super-strong. But once we have our third T-spin, we have many lanes to counterpunch from other than columns 9 and 10. The primary strength of this opening is giving another possibility for decks which may otherwise lack a strong T-spin opening.

Enough talk! Let's grade:

Damage: B+
Speed: A-
Followups: B-
Counterpunch: B
All-clear: C-
Anti-all-clear: A
Flexibility: A-
Explosiveness: A-

Now let's look at TvT opening matchups, theory-Tetris-wise. + is "slight advantage", +++ is "major advantage".

Tetrises: ++
Izzy: - We zone out their all-clear advantage mostly, but are vulnerable to quick 15s, and they have stronger followups going into midgame.
OJ: +
WumbOJ: - We're similar to the WumbOJ, but are vulnerable to its all-clear and have weaker followups from deck 3 onward.
Ace: +++
Long Combo: +
Left-O: + Two extra damage to start, somewhat better counterpunching.
Jail: ++  We hit just a bit harder and might just all-clear them for a quick win at 25.


Conclusion:

This is a nice opening to have in one's pocket for a difficult first deck when one can't Izzy or WumbOJ and doesn't want to Ace or Long Combo--in optimal play, it allows us to mix in a T-spin opening where some players might always go for an Ace, preventing us from being consistently blind-countered. It's also nice to have against Puyo. But we should generally choose to Izzy or WumbOJ instead when our first deck makes one of these possible.