The path to Ridley's room will start with a single one-way door (otherside is always grey). The path continues through more ominous, empty, one-way rooms, with the door behind you closing grey and the door in front of you pre-opened.

Ridley's room will be 3x2. Cave like, irregular ground, lava is occassionaly higher than the lower parts of the ground. Walls will be irregular too. Exit Door on middle left wall, closes when Samus comes close and Ridley attacks, entrance door on bottom right wall, closes grey when Samus enters the room.

The room will appear uninteresting until Samus attempts to leave, then the exit closes and Ridley charges from out of the wall.

Now, for Ridley himself...
Decrease main body damage to 78 (120)
Increase health to 61A8 (25000)
Damage multipliers: 1, 1, 2, 2, 0, 0, 1, 1, 1, 1, 2, 2, 3, 4, 0, 2, 0, 0, 0, 6, 0, 0

Attack changes:
	Tailbouncing
		Remove blind spots. Probably make the tail stab at Samus between bounces, if she's nearby
		Make bounce movement more eratic (higher probability of not going towards Samus) and more intelligent (don't face Samus if near the edges)
		Extension: Stabbing at Samus extends the tail, stays extended until the ground is hit.
		Mess around with speed values for interesting stuff
	U swoops
		Make the path more flexible, not predictable
			Retain the U shape, but larger for the larger room. Higher speeds at the bottom of the swoop.
			Start at a pre-chosen offset based on Samus's position (something like Y = 180 + (Samus position - 280) / 4, X = (side facing lookup) + (Samus position - 100) / 2).
			If Samus is in an invalid position, don't U swoop. Probably limit to: 4 - 10 blocks right of Ridley, 6 blocks min. below Ridley
			Angle starts directly downwards, moves towards Samus and accelerates at a rate depending on Ridley's speed (increase both alpha and acceleration) and Samus's Y position (higher = higher alpha, lower acceleration). I'll leave it abstract like that, it should work great with good values, I think.
			After passing Samus, pull up gradually, depending on speed byte.
		Abort if Samus is obviously dodging it (Samus's Y - Ridley Y, If moving right, + SamusX - RidleyX, if moving left, + RidleyX - SamusX. BMI to abort)
			Go to the far corner instead, turn around, immediately breath many fireballs.
	Fireballing
		Reduce invincibility time from fireballs
		Add a many-fireball without ground spread option
	Add new Ramming AI (or just massively tweak grabbing AI)

Tail changes
	Missile blocking
		Might simply remove it, and beef up the flinging towards Samus