Squad 51 vs. the Flying Saucers Review (Salt_Sudoku)
tl;dr If you like the settings/theme/presentation (which you probably do) you should probably get this unless you dislike horizontal STGs/SHMUPS or one that is mechanically simple in general.
If you scrolled down this far you're already sold on the presentation/aesthetics/setting so I'll focus on gameplay and content related things.
There are 11 levels which will take you about 90 minutes (this includes like 10 minutes of cutscenes) to clear in one non-death loop through the 11 levels. A good handful of them have end-stage bosses, but some of them end just by reaching the end. Some levels are shorter and longer than others, and there's a 2 level stretch with a level gimmick of a more zoomed in camera/larger ship as a "gimmick" if you consider it that, but everything else is general affair. You get ranked with a score and star rating at the end of each level (there's also 3 "hidden" collectibles per level). There are two modes of play: Normal (Level Select playthrough) and Resistence (Continuous playthrough that gets harder each loop through).
Before each level you get the option of slotting 20 different upgrades into your ship. These affect everything from the size of your ship's hitbox (it's visible in the Equip screen), damage/fire rate, armor (health pool), and how much damage you take from enemy fire and collisions (you can even negate this with 3 upgrade slots to completely nullify all non-head-on collision damage). You unlock new upgrades and upgrade slots by meeting a specific total score amount on the current playthrough through the 11 levels.
Your ship controls are simple and basic STG/Shmup affair. You only have one straight-forward shot type without upgrades, but you can equip up to two different special shot types as upgrades that can be used temporarily when they are charged up by damaging enemies. These include a single high damaging bomb drop, a gattling gun/rapid fire, and a behind the ship fire flamethrower volley. You have an Armor health gauge as well, so you don't technically die in one shot, but it does get cleaved off in huge chunks, so you really only get 2-3 hits total off even the most minor enemy fire. Certain environment collisions and attacks will still one shot you. Scoring is really simple, you just get a simple chaining bonus off continuously killing enemies within a short time as long as you keep the combo up. There are also extra lives/extends that you can score-up to.
Difficulty isn't anything special for a Normal mode clear, if you can make it through even a few stages in a CAVE game you should be fine here. Outside of a few bosses in the latter half of the game, there aren't any hard patterns, so it will be mostly score routing and basic level memorization. You can even enable Infinite Lives in the options menu and there's a generous checkpoint system so you can even credit feed to your heart's content. Dynamic difficulty and looped rank increases take effect in the Resistence mode which gets a lot more challenging so you'll probably spend most of the time in that mode after you're first normal mode clear. Resistence mode is the "Standard" mode and the only one that supports leaderboards, since Normal is essentially a level select unlock and practice mode. Also to note, that on restart you even get that option to auto-skip cutscenes as well as skip/disable any event related NPC dialogue that has already been played in the current run up to that point for your sanity.
Other general things:
- Any enemy that comes on screen is indicated with a small circular blip for a small moment before it spawns to avoid cases of being sniped by a spawning enemy on the left/right side
- There's maybe 2 or 3 "GOTCHA" moments total throughout the entire playthrough that may catch you off guard if you're sleeping, but nothing major
- The game only supports up to 1080p native resolution, but the game's art style and presentation doesn't make this a huge issue when upscaling to higher resolutions
- The game has a 30 or 60FPS cap
- You can select either the original Portuguese audio or an English dub
- There's a few accessibility options like permanent auto fire (you don't even have to hold the button to continuously fire), visibility adjustments, and subtitles