Levels
Waves of aliens dive side by side from the top, left to right, brake at the bottom and fly back up. The next wave comes when the last one is gone. Timing and speed are fixed in the game (kami_* settings).
Saving
Workflow: save in PICO-8 → edit here → save → load dgalaga in PICO-8. Saving in PICO-8 with an old cart in memory overwrites the levels.
Levels live in map rows 0–31. Do not paint there in the PICO-8 map editor.
No PICO-8? "Load online cart", build levels, "▶ Play in browser" (opens the game with your levels in a new tab; works on the web site, not from a local file). "Download cart" saves the cart with your levels to share them.
White frame = visible screen (128×128), around it 32 px of the invisible margin. Click a curve to select its stream, drag the curve to move the whole stream, drag a point to move just that point: ● anchor, ○ control point. At the end of its path an alien flies to its slot (big aliens roam, bonus aliens leave). Bonus preview starts without the game's "bonus stage" wait.
Formation
Pick a kind, click slots: they get the selected stream (click its curve to select it). Right click empties a slot. The number = stream; a stream fills its slots row by row from the top left. Each row is centered on its own (a row of 4 sits between a row of 5).