Let's start this one with a genre definition.

Metroidvanias are platformers that encourage non-linear exploration in which players search for a series of unlockable abilities that allow them to access parts of the world that were previously off-limits. All metroidvanias have boss fights. Most are 2D. The genre's name stems from its pioneering franchises: Metroid and Castlevania.

Phew. The opaqueness of the world's most popular form of entertainment never fails to amaze me. Now that we're on the same page, let's talk about Hollow Knight.

Hollow Knight* is the best metroidvania of all time. If you don't want to take it from me, take it from resident metroidvania expert Russ Frushtick of Polygon.com. Or... just about anyone in the industry, for that matter. Hollow Knight's charming 2D art style, rich and mysterious world, souls-like upgrade economy, satisfying progression loop, and often eye-wateringly difficult boss fights make it so. It innovates while staying true to its genre's roots. It holds elusive secrets around every turn. It challenges and delights. It gives. And boy, oh boy does it do its fair share of taking.

You play as a cute little bug boy with two pincers, one sword (which - in the miniature world of Hollow Knight - is actually, endearingly just a nail), and a desire to uncover the forgotten realm below Dirtmouth, a ghost town built on the ruins of a lost society.

You set out to explore its maze of caverns, discovering new areas, mapping territory, defeating foes, collecting currency (known as "geo"), buying upgrades, and saving wormies throughout the game's rich, non-linear world.

It's a classic metroidvania in a lot of ways. There are hidden areas in almost every cavern that you'll stumble upon. There are boss fights - both optional and mandatory. The game mixes in non-boss enemies with increasingly difficult platforming sections to reach checkpoints and earn abilities that allow you to traverse previously unreachable areas. Throughout your journey, you earn items and charms that will imbue your character with special abilities. You meet a cast of NPCs along the way that run the spectrum from creepy to cute to downright strange.

Oftentimes, metroidvanias feel unnecessary to me. The non-linear format does not appeal to my desire for order, and it's easy for frustration to start creeping in. While I felt my fair share of frustration while playing Hollow Knight, the game earns its reputation with its rewarding and wondrous exploration and immense attention to detail.

I treated much of my time with Hollow Knight as a meditative way to get over my issues with the genre and find joy in simply exploring the beautiful world that developer Team Cherry designed.

If you want to read more about how I feel about the game's boss fights, see my essay on the topic. TLDR: they are completely electric. Rhythmically satisfying, flow-inducing, and in most cases extremely difficult - Hollow Knight's boss encounters are one of the game's brightest facets while at the same time representing a major barrier to entry.

Since Hollow Knight does not offer accessibility features to customize its difficulty, it limits its playable audience to only the most die-hard metroidvania fans. Folks who know the language of the genre and who enjoy spending hour after hour on the same boss, climbing the mountain of difficulty ever so meticulously to eventually eke out a hard-earned victory.

I used a guide to get through a lot of the game's exploration beyond the ten-hour mark. Because, after a while, there was only so much meditative exploring I could do before I found myself running into a - sometimes literal - wall without any idea how to progress.

It's hard for me to write about this game. Maybe you can tell. I'm finding myself jumping around, wanting to go into detail here and there but worrying that I'll only be introducing ideas as inscrutable and labyrinthine as some of Hollow Knight's unmapped caverns.

In a lot of ways, it's perfect. At least, for what it is. There's so much here that I want you to experience. So much wonder. So many joyful exhalations after moments of delicious tension and seemingly insurmountable difficulty. That said, if you aren't either a hardcore lover of metroidvanias or someone with a whole lot of patience for difficult games, I can't recommend Hollow Knight in good faith.

Using a guide helps a bunch, so if you want to experience Hollow Knight's peaks without too much frustration, I would keep one close at hand.

The game earns a 9/10 that I still don't know how I fully feel about. I feel in discussion with this one in a way that might just point to its overarching genius. Or, perhaps, my own shortcomings as a player, or writer, or both.

If I had to use one word to describe Hollow Knight, it would be "atmospheric." However - just like I felt while playing - I still can't tell where exactly I fit in this game's expansive atmosphere.

Where it shines:

• Electric boss fights
• Fully fleshed out world
• Seamless exploration

Where it fades:

• Inaccessible
• Some gratuitous platforming