Elevator Action Returns (arcade) - 4/5
A sequel to the early 80s arcade game, Elevator Action - it's a relatively restrained shooter-platformer where you mainly move through levels by riding elevators up and down (falling more than your character's height will kill you). Has an especially strong presentation even among the other Taito arcade games of the era, with excellent music and amazing, detailed sprite animations. It's on the easy end for an arcade game, but your character's low HP and low amount of lives mean death is always fairly close even if you're doing well. Beaten without dying.
Osman (arcade) - 4/5
A kind of unofficial followup to Capcom's Strider, created by the original game's director / game designer after he left the company. It's a similar melee-focused platformer with a huge emphasis on setpieces and level gimmicks; its big unique element over Strider is its development of that game's afterimages, which you gain as you power up - pressing the attack button will have you place an afterimage at your current location, and boss fights and levels are balanced around using them to offset your character's otherwise limited attack range. This game actually has a lot of really good boss fights (which I wouldn't say for Strider), though they can be very punishing while learning the game since taking damage makes you lose your afterimages. Beaten on one credit.
Darius Gaiden (arcade) - 4/5
The third arcade game in the Darius series and the first I've played with any degree of seriousness. It constricts the game view to a single monitor, unlike the previous games, and adds in screen-clearing bombs. I really like the free-form shooting action in the Darius games, and the way they emphasize aiming your missile weapons carefully (often through point-blank attacking enemies) due to their high damage and enemies' relatively high HP. The boss fights, with their multiple distinct phases, exciting attacks that feel like an early precursor to bullet hell shooters, and multiple destructible parts that affect the bosses in various ways if destroyed are probably some of my favorite in the genre and clearly the highlight of the game. This is one of the easier arcade shooters I've played (though recovery on death is punishing due to how important upgrades are, the prevalence of durable shield powerups offsets it) but is extremely enjoyable nonetheless. Cleared on one credit.
Assault Suit Leynos (PC) - 4/5
Remake of the Genesis game Assault Suit Leynos / Target Earth, the first in the Assault Suit series - a line of mech-themed shooter-platformer games featuring inertia-heavy controls (to simulate the feeling of being in a mech), relatively methodical gameplay, and levels focused around completing various mission objectives instead of just fighting to the end. The original Leynos is an enjoyable yet rough game - maybe a little too ambitious - and this remake does a good job of ironing out the kinks: the addition of aim-lock improves combat tremendously, hard mode places a sensible limit on regenerating health, and the bosses and minibosses are somewhat more developed in this version (though not particularly the game's strong point, still). Giving the player the booster (which enables hovering and newly-added dashing) and the shield from the beginning of the game instead of making them later-game upgrades is fun, though I feel the shield is a bit overpowered (there is a strangely unlockable option to limit its durability, which should have been the default), and some of the early levels have their impact reduced due to being able to use the booster.
The game has two modes - arcade (loosely based on the Genesis game's level layouts with heavily reduced difficulty and enemy counts, but has a lot of new elements, new minibosses and bosses, and voiced dialogue) and classic (sticks closer to the Genesis game, is still overall easier). Arcade is good, but classic is definitely the meat of the game; it loses something without the hordes of semi-random enemies the original game and classic mode stick you with. Beaten without dying on both arcade mode and classic mode.
Really good month for games. All four of these games are honestly among my favorites now.