The Giant Bow and Arrow
Use it to enter the princess' room at the castle on Arturus. Take the rope from the right side of the Mill, and tie it to the giant arrow. Aim up and left, and click to shoot (you get as many shots as you need). If you hit the door to the Princess Tower, you can walk up the tightrope to get the Letter from her bedroom.
The Ice Arrow
On the Fire planet, defeat the Dragon by firing the Ice Arrow into its open mouth (three separate times). To fire an Ice arrow, click on the icon in the lower left corner, aim for his open mouth, and click again to fire.
*You can only use the Ice Arrow when the dragon is "asleep" for a few seconds, with its eyes closed and mouth open. You create this by climbing OVER the dragon to the back, then slipping past the spike tail to flip the lever on its back. VERY QUICKLY jump back in front of the dragon and shoot an Ice Arrow into its open mouth. (You have to do this whole process three times.)
(see related questions)
You shoot the arrow at the tower to the left then jump on the rope and go in the tower. hope this helps!!
The crossbow will let you create a way into the Princess tower. Get the rope from the water wheel at the mill and tie it to an arrow. Aim up to the left and shoot until you hit the door.
You just aim and click. The only time it is effective is when it goes into the dragon's mouth when there are no flames there (you have to put it to sleep for a second or two). Climb around the back, dodge the spike ball, and pull the lever. (see related question)
on astro-knights.
There are no fish on Astro Knights Island. There are Space Sharks around the Ice Planet at X-73 Y-83. To defeat them, shoot them and lure them to the Black Hole at X-85 Y-47. (see related question)
Dodge them or shoot -- click your mouse to shoot, and watch out for pieces. (If you take a Space Shark to the Asteroids, he swims right through them!)
To reach the left-side tower of the castle (the Princess room), you need to use the rope from the Mill. Tie it to the arrow on the giant crossbow and shoot it left and up to hit the tower door. (You get many tries.)
You shoot them
get the rope from the wodden thing in the mud next to the mill, then put the rope on the arrow, and shoot it towards the castle.
*You can only use the Ice Arrow when the dragon is "asleep" for a few seconds, with its eyes closed and mouth open. You create this by climbing OVER the dragon to the back, then slipping past the spike tail to flip the lever on its back. VERY QUICKLY jump back in front of the dragon and shoot an Ice Arrow into its open mouth. (You have to do this whole process three times.) To shoot the Ice Arrow, click on the icon at the lower left, and aim for its mouth, then click again to shoot.
Go behind the monster, climb on its back, pull the switch, then go in front of the monster and shoot the ice arrow into its mouth. Do this 3 times and you will defeat the monster.(see the related solution)
You have to move fast once you throw the lever on the dragon's back. You only have 5-10 seconds, and missing more than once will probably force you to reset and try again.