The three "in-game games" included in Retro Game Aliens is 
 developed in the early 1980s as Newly developed titles that are heavily influenced by the PC adventure games that have been released.

Any old Japanese gamer (including former gamers) will know what those "originals" are. 

The most important element when creating a "game like old games" is graphics.

Because we want players to know that the moment they see the screen, it's a Legacy of the past, not a modern game.

The graphics of "Royal coffin" are based on those of the hobby-use computer "PC-6001" (SCREEN MODE 3) released in 1981 by Japanese electronics manufacturer "NEC".

The resolution of the full screen size is 128×192. Since the same information is duplicated in the horizontal direction for each dot, the display size is equivalent to 256x192.
4 colors out of 8 colors can be displayed simultaneously. The composition of colors used is fixed as a palette.

The graphics of "Nymph Street" and "Waiting at the Pavilion" are based on those of PC "PC-8801" , which was also released by NEC in 1981 for business use. As an aside, the PC-8801 soon became a gaming ｰ model. It became decisive with the successor model "PC-8801mk2SR" released in 1985).

The resolution of the full screen size is 640x 200. Since the same information is duplicated vertically for each line, the display size is equivalent to 640x400.

8 colors can be displayed simultaneously. When expressing neutral colors, it is necessary to tile the colors.

In "Retro Game Aliens", the display area of the in-game game graphics is fixed at 960 x 570.
Therefore, the graphic of each title is an enlarged display of the data created with an aspect ratio that fits that area.

The occupied area when the created event graphics are displayed in the same ratio in the full screen size of each PC looks like this.

You can see that these sizes are not unreasonably determined, and can be displayed reasonably on the actual device.

The graphics of previous video games, which allow you to mimic the style of anime and movies, evoke a mysterious, timeless nostalgia.
Our goal is for many gamers to experience it in the form of visual novels.