The creature in the volcano does not seem to have a name. It is called the lava snake, the segmented creature, the eye creature, and the rock worm. To get past it, jump over it while it is completely extended. Wait for it to roll toward you in a circle, then step back. When it rolls out flat, quickly jump over.
On the Fire Planet, jump from rock to rock as they are lifted and dropped by the geysers. Jump when the next rock is below you, even when you can't see it. For the 6th rock, jump when both rocks are moving downward.(You will land on the rock as it falls under you.)
You keep pushing until it finally collapses (it is dirt, not rock).
It isn't rock, it's dirt. (Surprise) You can push hard and it will collapse. == ==
The wall on the left is made of dirt, not rock, and if you push hard it will collapse.
The creature (variously called the rock snake, eye monster, caterpillar, or rolling monster) unrolls to attack. When it rolls toward you, jump back as it fully unrolls. When it is flat, quickly jump over it.
The eye creature / lava snake / segmented monster / dice monster / rock monster is blocking your path in the volcano. You can't jump over it until it rolls toward you and then unrolls flat on the ground.
The creature (variously called the rock snake, eye monster, caterpillar, or rolling monster) unrolls to attack. When it rolls toward you, jump back as it fully unrolls. When it is flat, quickly jump over it.
The giant asteroid is at X-11 Y-84, but you can only remove the Golden Key when you have beaten all three planets and have all three space knights with you.
The wall that blocks the passage on the left side of Mordred's underground lab is NOT rock, but dirt. Push against it and it will fall down.
On the lava geysers of the Fire Planet, you will need to jump from the 5th to the 6th rock platforms when they are BOTH moving DOWN. (You will land on the rock as it is falling under you.)
Just wait until the 5th and 6th lava rocks are both moving downward, then jump. The sixth rock should fall right under you.
You have to beat the Fire Planet and the other two (Ice, Jungle) as well, and have all three space knights with you to rescue the Princess from the Binary Bard. The first step on the Fire Planet is to jump the lava rocks. For the final jump, 5th rock to 6th, the secret is to jump when both rocks are moving down. For the remainder of the planet, see the related question below.