This one’s kind of special. From the Retronauts news piece:

What’s this? A horizontally-scrolling sci-fi shooting game, originally developed by Compile for Sega’s SG-1000/3000 console in 1985 and ported to MSX the following year; the basic shoo-and-dodge gameplay is augmented by a weapon power-up system that sees the player collecting numbered chips to advance a lengthy power gauge and gain access to the various shot upgrades (or downgrades) that correspond to each unmarked square on the gauge.

Why should I care? Very rarely did Compile attempt the horizontally-scrolling format, but all signatures are here: best-case-scenario technical performance, a risk-reward about exploiting the invincibility gained from grabbing chips, and stage/weapon/enemy volume that verges into overkill territory.