Rainbow Lines are lines drawn by the stylus on the touch-screen of the Nintendo DS in Kirby: Canvas Curse. Kirby develops the power to use Rainbow Lines after serendipitously obtaining the Rainbow Paintbrush. The use of the rainbow lines may require constant monitoring of the ink gauge.. Ink replenishes quickly while Kirby is on the ground, but slowly while suspended in the air or riding rainbow lines. Additional ink styles can be unlocked in Medal Swap. These include a black and white Zebra Line, a studded Bead Line, and a primary color studded Tropic Line. The ink styles can be changed at any time in the Options menu.
Rainbow Lines are mostly used to guide Kirby's movements. Due to the Ball form's limits, the lines are his only way to get over walls and open pits. Kirby will follow the direction the line was drawn. Loops can be drawn to speed Kirby up as though a dash move has been activated. Lines drawn too steep will ricochet Kirby's direction of travel. Whenever a second line is drawn the first will begin to disappear quickly.
Using rainbow lines under water inverts the mechanics somewhat. Since Kirby's ball form naturally floats, lines need to be overhead to guide him. A field that appears to be similar to water can be found in several levels, these fields will not generate rainbow lines. Rainbow Lines can also be used to block wind or currents from contact-activated fans to free Kirby's movements.
Lines can block on-coming projectile attacks from Shotzos, Flame Shotzos, lasers, and more. Clever use of the ink can both protect Kirby and provide the rail to travel on. Some scenarios may be best confronted by using "V-shaped" or "C-Shaped" lines with Kirby traveling in the enclosed portions. Some enemies are able to attack through rainbow lines and even destroy them. Of all the boss fights in Kirby: Canvas Curse, only the Drawcia battle requires the use of rainbow lines.
- Main article: Rainbow Run
Line Trial is a mode of Rainbow Run in which ink usage must be minimal in order to receive the medal prizes. The courses are from areas of the main game levels, but replacing the World of Drawcia with unlockable courses. The top screen replaces the map with a large ink bottle filled with Rainbow styled ink. The bottle has incremental markings on it, to gauge usage.
- "When you slide your stylus across the Touch Screen, you draw a rainbow line." —Kirby: Canvas Curse manual (page8)
- "Each time you draw a rainbow line, your ink gauge on the Top Screen will be depleted. " —Kirby: Canvas Curse manual (page9)
- "The gauge refills automatically whenever you aren't drawing lines. When Kirby is on the ground or on a ledge, it refills more quickly." —Kirby: Canvas Curse manual (page9)
- "Draw a line up to a high ledge, and Kirby will roll right up to it." —Kirby: Canvas Curse manual (page8)
- "When Kirby rides on rainbow lines, he rolls in the direction the line was drawn." —Kirby: Canvas Curse manual (page8)
- "When Kirby hits a vertical rainbow line, he rolls in the opposite direction." —Kirby: Canvas Curse manual (page8)
- "If you draw 2 rainbow lines, the first will disappear quickly. To avoid this problem, instead of drawing two lines to protect Kirby, draw one line that protects him from both sides. " —Kirby: Canvas Curse manual (page24)
- "When you want Kirby to dive underwater, draw rainbow lines down from above to guide Kirby deeper into the water. Otherwise he will try to surface." —Kirby: Canvas Curse manual (page24)
- "Draw rainbow lines to protect Kirby and get him safely past the laser." —Kirby: Canvas Curse manual (page16)
- "Use rainbow lines to protect Kirby from enemies and shots." —Kirby: Canvas Curse manual (page8)
- "Instead, draw one line that wraps around Kirby to protect him from both enemies." —Kirby: Canvas Curse manual (page24)
- "Also, rainbow lines cannot protect against some falling enemies, like (Thudd)." —Kirby: Canvas Curse manual (page16)