@Abc_42: There's a couple of reasons:
- Has way too much health for a miniboss.
- Takes an extremely long time to destroy (without the charged Ray Arrow, Metal Anchor, or Rekkoha).
- You fight this thing five times and one of those fights is an autoscrolling section above a pool of instant death lava where you have to dodge the snake, its bullets, and several enemies in a limited space.

EDIT: I went through this stage with armorless X for the first time, and taking this thing out with no special weapons is not as bad as I thought it would be, but it's time-consuming. I still say it has too much health, and the autoscrolling section is still annoying, especially if the Nightmare Bugs are there.

Really cool fight, idk why people hate this thing

They call it a snake, but to me it looks more like a donut.