Net Yaroze Round-Up Vol. 7!

Grave Pobbery (Masahiro, 1997)
This game is very unpolished, but mechanically it seems to be mostly finished. It's a pretty simple game in which your little polygon man enters stages that each contain a few stone blocks. Using your pickaxe, you smash every block in the stage, and fight off the ghosts and snakes hiding within, either by repeatedly hitting them with your pickaxe, or by using items, also found inside the blocks. There's crosses to get rid of ghosts, and bombs to kill the snakes (and handily, destroy any blocks caught in their blast, too).  It's a mildly amusing game, and its simple nature and tiny amount of assets used make it feel like the kind of thing someone might make for a quick game jam today.

Alien Looter (Ben James, 1998)
Alien Looter is a pretty simple concept: take Space Invaders, add power-ups and remove the dan kire so that the player can shoot as quickly as they can press the fire button. The result is a game where stages last only a few loud and cacophonus seconds, and you can blast through fifty or more stages in only a couple of minutes.  It's nothing especially fancy, but it is a lot of fun while it lasts.

Oyaji (T. Munemasa, 1998)
This is a weird one: you play as an old, balding man wearing only a pair of underpants, and you're trapped in a brick maze with some hovering satellite dish robot things. As far as I can tell, your task is to smash all the robots, but awful collision detection coupled with your long, slow attack animation make this very difficult. Oyaji is graphically impressive with its texture maps and such, but not very fun to play at all.

Diver (Nahoisa Kamei, 1997)
Diver looks and feels like a game from a 1980s 8-bit computer, specifically the kind popular with Japanese hobbyists, like the PC88 and such. It's a very simple game: you play as a diver, diving into the sea to get piles of gold, though you can only stay under for a few seconds at a time. Every time you get a pile of gold, another one appears, as well as a few more rocks to get in the way. The main problem with Diver is that there's not really any challenge, unless you play chicken and try to get multiple piles in a single dive, but there's no real reason to do this, since they'll only be worth one point each whatever you do. Adding a score multiplier or something to incentivise this kind of risky play would be a massive improvement.