Sonic and the characters and places within it belong to SEGA.  Also note that every boss
name present is purely fanmade.
Every boss here requires eight hits to defeat, except for one, which will be pointed out.
GREEN HILL ZONE:  EGG WRECKER
This boss has a really simple mechanic.  Hit Eggman while he's ccoming in, he's vulnerable
then.  You can land 5-6 hits then if you're good.  Then, run under a platform or jump over
his wrecking ball.  Overall, this guy's easy as it gets; if you can't win, you shouldn't
be playing.
MARBLE ZONE:  EGG TOASTER
Again, Eggman is vulnerable while coming in.  You can hit him once or twice while he's
flying over to you, and then once again while he's dropping fire.  Be swift when he drops
the fire; jump over to the other side of the arena.  He shouldn't give you too much
trouble, as long as you're careful.
SPRING YARD ZONE:  EGG SPIKE
Sometimes, when Eggman floats a bit low, you can jump up and hit him, but I wouldn't
recommend this, especially if you have no rings.  Otherwise, stand on one block and wait
for him to lunge at you.  When he does, walk to a tile beside you and hit him 2-3 times.
He'll eventually snap back up and break the tile.  There are 10 tiles in the arena, so
don't worry about falling too much.  Basically, repeat until dead.
LABYRINTH ZONE:  EGG RETREAT
This boss is the one you don't have to kill, and yet, he is considered the hardest.  I
can't offer much advice for this one, other than don't worry about drowning.  The only
disadvantage of letting the water get you is how sluggish it makes Sonic.  Overall, be
careful more than anything.  Watch out for the bullet shooters, and dare to wait at an
area guarded by two spears.
STAR LIGHT ZONE:  EGG BOMBER PROTOTYPE
You have two methods for hurting this boss.  You can either catapult yourself at him using
the spike-balls and seesaws, or you can lob the spike-balls themselves at him.  If you
decide to launch yourself, don't hit him more than twice, lest ye can sacrifice some
rings.  The only real thing to watch out for is the spike-balls; don't let one idle, or
it'll explode, almost guaranteed to hit you!
SCRAP BRAIN ZONE:  NO BOSS
Strangely enough, the hardest world has no boss.  However, Act Three is a water stage, so
be very careful at that.  Stop for air whenever you can, and regardless of where you think
the surface is, you can't reach it in time!  Just wait it out for an air bubble.  Practice
your water controls, there're going to be a lot of close calls here...
FINAL ZONE:  EGG FACTORY
Before you go fight the boss, take a second to appreciate his epic theme--I mean it.  Now,
when you enter the arena, don't get too comfortable.  Two giant pillars will shoot out of
the ground and ceiling!  One will be empty, one will contain the fat man himself.  Stand
between the pillars if you can, and hit the one with Eggman in it.  Then, a tesla attack
will fire, shooting 3-4 plasma bullets at you.  Find a gap between them and jump to dodge
when they start moving.  Then, the pillars appear again.  This one only needs some
practice.  Go get 'em, tiger, and congrats in advance on beating Sonic the Hedgehog.