In La-Mulana, you set out and explore inside ancient ruins seeking out the “Secret Treasure of Life”.
The game is a massive metroidvania full of cryptic puzzles, unforgiving platforming mixed with a lot of traps.

The first thing most people will notice about the game is it's movement and jumping mechanics.
First off: the movement speed might feel a bit sluggish at first for some people, but the game has a way to improve movement speed early on.
Second: when jumping in the air, there is almost no way to change direction, except if you've jumped straight up.
Some like it, some don't, some get used to it, for me personally, after getting used to it, I started liking it quite a bit, it's a mechanic that felt kinda right to me in a game like this.

As for the platforming, it's quite unforgiving.
Dying will certainly happen, but more often you will find yourself climbing back up a place you've recently fallen down from because of enemies or traps.
The game still has a couple of questionable level design choices, but for the most part it's honestly quite good.

The boss fights are brutal for a first time.
You will likely die to most bosses, and multiple times too, but all bosses have fair and learnable attacks, and feel satisfying when defeated.
The only problem I have with the boss fights is having to walk all the way back from a save point after dying, which is not always the longest walk, but it can be tedious at times.

The thing you'll most likely be spending most of your time on in a blind playthrough are the puzzles.
Some of the puzzles are easy to solve, but in the later stages of the game they can get really cryptic.
It's reccomended to take as many notes possible, as you'll be needing almost everything to solve some of these really cryptic puzzles, and even then, it might still take a while.
Brute-forcing is very possible, I spent quite a bit of time running around the ruins doing seemingly random things, and it works a lot of the time, but this shouldn't be a strategy anyone should be fully dependant on, since not all puzzles are brute-forcable.

The game has a lot of lore too.
At first sight there might not be too much to it, but as you progress through the game you'll read a lot about the history of the ruins, and a lot of it is very intersting.

It's is not for everyone, it's difficult and very time-consuming, the puzzles may not be everyone's thing too, but for those who enjoy it will get a lot of value out of it.
It has a lot of moments that had left me satisfied, the level design, even if questionable in some places, is mostly very clever.
The soundtrack is really enjoyable, the visuals look charming and just overall the game has a lot in store.

This game is my personal favourite metroidvania, and one of my favourite games of all time.