These are put in as Weakest to Strongest. and this was taken from the Fandom Wiki. I really put work into this so please dont steal this. and I hope you have a wonderful time reading this

the Blue Eyed Pumpkin would most likely belong to Stickula, the blue stickman. or stickmam.

Stage 1:
Shotgun
Shotgun is just Pew but its 3 instead of one.

Stage 2:
Burst
MULTIBLE Shots are fired.

Stage 3:
Bounce
This is just Pew and that one rebound gun mixed together.

this Red Eyed Pumpkin is belonged to Dr Jekyll (Or Mr stick)

Stage 1:
Pew
just Basic Orbs. nothing else

Stage 2:
Saw
a Saw encircles the boss and if a player gets near, they get hurt. also the boss is kinda invincible. deal damage as you can!

Stage 3:
Ring
A orb will explode into millions of orbs called a Ring.

This Yellow Eyed Pumpkin belonged to Pumpkinstein.

Stage 1:
Pew
This is just a orb, just like the Dr Jekyll/Mr stick's pumpkin

Stage 2:
WALL
WE WILL BUILD A WALL
all jokes aside, this is a wall that is the size of 2 players and moves SLOWLY, this deals tiny damage but the player can jump on it, and when you shoot it, the wall will start breaking with each shot you hit it with

Stage 3:
Beams
Its a lava lazer gun but theres more and you got 1 second to move!

Stage 4:
Another WALL
WE NEED TO BUILD A WALL
(read last one I aint repeating it)

This Rainbow Eyed Pumpkin is the Spooky Disco Pumpkin.

Stage 1:
Rainbow Pew
just a Pew

Stage 2:
Waves
(Dependant on where the boss is shooting) You have to avoid AND jump to save yourself from the floor rising and killing you

Stage 3:
Implosion
The Boss will shoot a random place, it blows up, and you got 3 seconds to get in the circle.

Sometimes the boss's healthbar will not drain as players attack the boss
Sometimes players cannot obtain the pumpkin due to desnyc
If all the players kill each other before anyone collects the pumpkin, the boss music will persist on into the next level
On very rare occassions, 2 players can collect the pumpkin and become the boss due to desync
Sometimes if players maps aren't synced correctly someone can become a boss in a completely different level
Blue boss's Bounce attack doesn't deal damage in online lobbys
Commonly the bullets will not turn white and can still harm other non-boss players

Thank you for Reading my guide and I hope you learned about how to avoid bosses!