Seiren posted:

This guy....not threatening at all? I disagree, but eh. This part of the game is designed to wear you down and force you to use supplies to keep going. It is very much a sort of "final boss" for Disc 1, and serves as a painful introduction to Disc 2. You have a long way to go before you get any rest, any opportunity to really restock on items and ammo (aside from 9mm PB). So it's actually quite nice that the game beats you over the head with the whole "prepare to go to the shelter" phase at the end of Dryfield.

This boss is actually extremely dangerous, but that's primarily due to the location you're fighting in. I also heavily doubt it's a spoiler to mention that you have to fight it twice, because we can almost plainly see its red eyes and it getting back up after it initially falls.

At its most basic, yes, the room is in fact a ring with corners. Near each corner is one of the four mentioned barrels. Each "side" of the ring is an extremely narrow walkspace; just wide enough for both Aya and the Blizzard Chaser to fit through side-by-side. This greatly limits your maneuverability, and combined with the camera angles you're given, it's very difficult to keep an eye on the boss for long. The darkness only adds to that, making him surprisingly difficult. Its' agility works greatly in its favor, allowing it to quickly get-in and out, while you struggle with tight hallways, the darkness, and awful angles of sight.

The Chaser itself has multiple attacks; most which are executed from a running start (and it will be running around for 95% of the battle). It has a standard pounce, in which it leaps forward, knocking Aya down and sends her skidding across the ground for a distance. This can be avoided either by luck, or running under it in the direction it's attacking from. Avoiding by luck grants a very short window with which to attack it from the front, side, or back depending on where it landed in relation to Aya. It strikes at Aya's position from when it initially jumps, and covers the entire width of any "side" of the ring (it sort of swings its head & neck around when it lands). Avoiding it by rushing it provides a slightly longer window to attack it from behind, for a moderate amount of extra damage. Trying to avoid it by running in the opposite direction -can- work, but it sets-up for a close-range attack (it skids a short distance when it lands). It can also "disappear" from the ring temporarily -- it climbs on the heavy excavation equipment in the center of the room and pounces on Aya from there. This is its least dangerous (but most damaging) attack, as it telegraphs the motion with a loud moan, sigh, grunt, or whatever you want to call the noise it makes. Either way it sounds weird and staying on the move means it'll miss, opening up an opportunity to attack it from the front, as it seems to always land facing Aya. Finally, it has a melee attack, which it only uses if Aya is close, and the Chaser happens to not be running. It bites & grabs Aya by her neck and shakes her around a little bit. Since that's rare, it's likely to take you by surprise. It deals a moderate amount of damage, and it can inflict Poison status (this may only apply to round 2, I forget). You can shake your way out of this to reduce the amount of damage you take. Either way, you get poisoned, it has quite a good amount of time to work with to deal extra damage to you, and running around more increases the damage you take. If it happens to miss this attack, it's going to start running almost immediately after, so take a shot or two and get ready for the next attack. In Nightmare mode, assuming you haven't acquired better armor, every attack will kill you without Antibody Lv.3, and the big pounce will always kill you.

As for the four barrels, their HP is fixed at 30, even in Nightmare, which doesn't seem like much, but they have ridiculous defenses. You'll find yourself only doing 2~3, so you need to mentally keep a note of how damaged a barrel is if you expect to damage the Chaser with it. The M950 auto-pistol is incredibly effective for this. In higher difficulties, the barrels are extremely effective at dropping it, as their damage isn't scaled by the difficulty level. It is more economical to damage the barrels, then detonate them when the boss is near for...I actually forget how much damage, but it is extreme...and the blast will knock it down, allowing for some free criticals, or a spell or two.

Between rounds, all you get to do is loot the body of the Jumper Plug and Kyle's glorious P229, pretty much the 2nd best handgun in the game...unfortunately you won't be able to equip it, or even recover. So try to end the first round strong, as Round 2 begins immediately after the scene.

While I'm spoiling a little bit, its attacks do not change. It has the same set of moves, and the same general patterns as it did in Round 1. However, in Round 2, it moves and attacks faster, has substantially more HP, but does less damage. Applied to Nightmare, that means you can survive all but the big pounce without Antibody. With, you can even survive that (but only barely, and this assumes you've used Protein Capsules too).

If you don't like walls of text breakdowns about boss-battles, here's a summary: This guy is a complete asshole, but it's more due to the environment and not the boss itself. Its attacks are all relatively easy to avoid, and it has some very significant weaknesses to Wind-based energies. As Crowe mentioned, it is susceptible to Poison itself, but to lesser extent than the Fire Breather. While normally difficult to use during the battle, a very well-timed Plasma can knock it flat out of its normal pouncing attack, meaning free criticals while it scrambles to get back on its feet.  Apobiosis also works superbly, dealing excellent damage and paralyzing the boss for around 5 seconds...more than enough time to detonate a barrel on it.