Just some quick tips for anyone, whether familiar with Metroidvania titles or just starting in the genre. This guide won't go over controls and such, since that's covered in-game, but can give some good general tips.
General Gameplay Tips
If you've come from any of the 2D Castlevania titles you may have immediately tried some of these, and been rightfully excited to see that Bit Kid decided to code their game such that these tactics are still a thing.
- If you attack as you're coming down from a jump and you're hitting attack fast enough you can immediately attack again upon landing. This allows you to hit some enemies far quicker than you normally would be able to. (Mainly larger enemies, but if you're hitting attack just before landing you can hit some shorter enemies twice as well).
- You can press attack and back-dash at the same time to do a retreating swing. This is very helpful for those little kobold buggers that like to shank you in the face while you're still locked into an attack animation otherwise. (Also, exceptionally useful against those dang snakes and their charging at you, lol).
- You can attack "downward" with some weapons (the starting sword for instance) by aiming a diagonal downward away from you. It's not a full on Shovel Knight style down-stab, mind you, but it can be helpful for getting an extra hit in on some enemies before they can get in range for damaging you (like the little beetles circling some single character wide platforms).
- A quick tip about familiars is they work much like they do in the 2D Castlevania games, they level up as they deal damage to enemies. I'm unsure if there's an upper limit to the level of these familiars as I only have one so far and it's now level 17 (and counting!) and it definitely seems familiars level especially fast with the killing blow on enemies. This particular familiar is tied to a piece of equipment, I don't know if all familiars are, or if there even are any other familiars.
- Another, non-combat related, tip is to jump around at pretty much any walls you find. Illusionary walls are a thing, and sometimes even lead to entirely separate secret areas with a few connected rooms and some extra items and such. (You may not have missed anything major in your playthrough, my procedural playthrough seed just had some in it so far).
Anywho, just some random tips for people. Hopefully these are helpful to people!