Dolphin

Dolphin (previously known as Misfire-Beta) is an opener developed by Kerrmunism, intended to be used mainly in TETR.IO for bags where Misfire isn't applicable. It's notable for having many freestyle ways to stack, as well as potentially being a (worse) alternative to MKO Stacking. The opener consists of a T-Spin Single, followed by a Single Double shape into a DT Cannon or Fractal, or a second bag STSD.

In all cases on this page, if you see a transparent piece, it means you should place it after the T piece in your current bag.

First Bag
The first bag will always be stacked like this. There's a number of dependencies, being that you need to be able to stack the pieces L, S and O in that order.

Second Bag
The second bag is mainly built using this method, forming a Single Double which all future continuations will be built based off of. In games that have 180 (such as TETR.IO), you'll be able to place your J after your L has already been placed, making the opener much more viable than in other guideline games.

You can also stack the second bag using these methods, though the follow-ups would be different.

There is one alternate stacking method in particular that requires a closer look however.

B.A.S.S Method
Standing for "Best Alternative Second Stack", this method gives you an immediate TSD for the second bag, with extra damage potential available. It also tends to be safer to stack when available.

Build the second bag like this, placing your S (or Z, if you put your S first on the other side) after your T

From here, you have various options available.

4-5 Stacking

Cut Copy

Fractal

T-Spin Triple

Double Triple Double

Trinity

Try to adjust the method you use to stack the second bag according to your opponent's game plan and your current board state.

Third Bag
There's various continuations that you can do after the second bag's main build, namely setting up a DT Cannon or a Fractal.

Fractal
A fractal can be stacked in the third bag using various methods. Namely, you just need to make the shape below, with the ghost piece representing any block.

Some examples are shown below.

DT Cannon
A DT Cannon can easily be built in the third bag, as long as you get your S before your I, and ideally your Z after your J.

You could also make a C-Spin after the DT Cannon, however in practice this is nearly impossible to accomplish without wasting a T and is impractical for actual usage.