This game has been updated a few times since the jam started and I'll probably keep updating it throughout. I'll continue editing this comment as I update the game.
Most recent update: September 11th
Changes so far:
Picking up guns no longer equips a new one if you have that gun already.
Reduced enemy counts and fixed soft locks in multiple levels.
Updated tutorial.
Updated menus.
NPCs are immune to player's attacks.
You can hold spacebar to swim up.
The earlier tomb levels have had their layouts edited to hopefully allow better use of the game's movement system
Unique summons now properly summon
Number keys can be used to select weapons
Changed the wording on some menu button to be clearer
Moved the merchant on the island level closer to where the player starts
Changed underwater movement to be less insane
FOV and mouse sensitivity can now be changed from the pause menu
Added motion sickness warning to the title screen
You can now "clear" a level by killing every enemy in it. Doing so will reveal how many secrets that level has and how many you've found, as well as (mostly) preventing the enemies in said level from respawning when you revisit it.
Added tutorial level to hopefully teach the movement better
levels with no secrets no longer show the secret counter
A number of other smaller things.