Black holes
Black holes are Wall-X's most advanced obstacle. They only appear in space stages, from Level 6 onwards. They pull a passing ball towards them and swallow one that gets too close to the centre. A ball that passes at the right distance gets its path bent and flies off in a new direction, like a slingshot.
How the pull works
Every black hole has a radius. Its pull reaches out to six times that radius from the centre and has no effect beyond. The edge of that field is shown as a dashed circle. Once inside, the pull grows very quickly as the ball gets closer: it's roughly inversely proportional to the square of the distance.
Black holes in the game have a radius between 20 and 29 centimetres. For one of 26 centimetres:
| Distance from centre | Strength of pull |
|---|---|
| about 1.56 m and beyond | no effect |
| about 1.3 m | about a third of Earth's gravity |
| about 1 m | about the same as Earth's gravity |
| about 52 cm | about 5 times Earth's gravity |
| closer than 26 cm | the ball is swallowed |
When the ball is swallowed the shot ends, but the stage doesn't restart; your drawings stay. You can't draw within 10 centimetres of a black hole's radius.
Using a black hole
Keep away
If a black hole sits on your path, the simplest answer is to route the ball outside its field, the dashed circle. Gravity differs by planet in space stages, so flight curves aren't like on Earth; check the gravity table on the Space page first.
The slingshot
If the ball passes along the edge of the dashed circle without getting too close, its path bends towards the black hole and it flies off in a new direction. It's an ink-free way to reach a hole behind an obstacle or to turn the ball downward. A fast ball bends a little, a slow one a lot; you control the bend with shot power.
More in this section
- SpikesTouch them and the ball pops and the stage restarts. Your margin is a few centimetres.
- PitsA ball that falls in is lost. Jump it, or cross it at speed.
- PipesTakes a slow ball from the floor and drops it from the ceiling. Speed is everything.
- GatesSlides up and down in front of the hole. When you shoot matters as much as what you draw.
- Wall behind the ballThe target is behind you. Send the ball forward, then bring it back.
- TrianglesTheir slope carries the ball upward. Used well, a free ramp.
- No-draw zonesYou can't draw in the hatched area. The solution has to live outside it.
- Rubber blocksBounces the ball without losing speed. Think of it as a spring you can't move.
- Magnetic floorsSlows a touching ball by 18 m/s every second. Cross fast or don't touch it.
- Sticky floorsThe ball sticks and the shot ends. Your drawings stay, though.
- PistonsExtends from the floor or ceiling and pulls back. You get past by choosing your moment.
- Ceiling targetThe hole is in the ceiling, not the wall. You have to send the ball up through it.
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