If you have a brandish line, which is basically the quintessential sword, on depth 27 after the second arena, you may use the charge to destroy the wheel barrows along the center, great for just speedrunning through the worthless section.
Also in addition to Judge's last tip, just try to water Vana's fire orbs because it'll allow for more damage from blitz to get past and it's good because it'll decrease the chances of you being lit on fire when he charges at you.
Also,
PSA: DO NOT THROW WATER AT THE ALREADY WET MASK IN PHASE 2 and 4! If you do, and if any teammates are near the mask when you water it again, they're in for a world of pain and fire and suffering and will die, and we all hate you >:V .
Also, if you use shivermister against Vana, you must know the pain of having someone using their really weak gun in comparison to Blitz Needle, and breaking your freeze repeatedly. Do not be this person and make every attack count and hurt, because the person who's freezing him is giving you the damn opportunity to.
Also, on depth 26, on the left path. No, you do not have to throw a water bubble in the top left corner room. Why? Because you can actually get close enough to the statue blocked by fire and pick it up without having to waste time throwing water at it. The same goes for the center water fountain surrounded by fire after the second arena on depth 27.
Also, I would advise just speedrunning through 24. 24 doesn't have much note worthy to waste time over. Also on depth 25, only do 6 rooms since you only need 6 sprites to get water. I suggest skipping the wheel barrow room on the left side and the room with a trojan and two silkwings on the right.