Trying to keep providing updates at a decent clip, even if I don't feel too great about the content in question! But it works, which is what matters at this stage.
So, this is really shitty - it's not a dynamic fight at all, and
the boss should really move to track you with its standard shots - but
it's recognizably a boss fight with its own mechanics. Dude sits still
and shits bullets until he decides to try to run you down, then covers
his ass during the vulnerable period after he finishes those shadow
charges by summoning that crazy arrow-rain attack. You need to look at
the layout of the projectiles and your screen position quickly to find a
safe firing position during that brief window of opportunity.
There are these eye-things on the floor that'll hurt you if you run into
them, and they're making the otherwise-optimal corner positions a whole
lot less desirable. You can shoot the eyes to destroy them, and they
even count as enemies, so they'll refill your energy - but these are the
only energy refills in a very dangerous fight, meaning you have to be smart about when to pick them off.
Not shown: if you pick all four eyes off, the boss starts using the
horizontal and vertical arrow rains simultaneously, instead of picking a
pattern at random. Don't get greedy!
This is, as mentioned, a shitty boss. This is Bed of Chaos levels of shitty boss!
But it's a boss. Which means I can build the furniture of a boss
fight around it. The kind of detailed, in-depth design that'd be
required to build a good boss fight isn't happening right now because
the mechanical fundamentals aren't solid enough yet - anything I do at
this stage is a shitty boss, so this is as good as any.
So my immediate priority is getting things in place for some sort of progression now.
The progression in question is: a key should be dropped in the Fuckton
of Ghosts Room, which is required to enter the Shitty Boss Room. Beating
the Shitty Boss will result in dropping a third weapon.
Some sort of placeholder inventory menu will allow you to equip the
third weapon, and that'll resolve an otherwise-intractable obstacle in
the snowy room.