Powerhouse

The Powerhouse era was the third era of Cartoon Network. It began in March 2, 1998 and ended during the early morning hours of June 14, 2004. It was succeeded by the CN City era. The last program to air under the Powerhouse era on June 14, 2004 was Captain Planet. "Screwy, Ain't It" was the slogan for the era (until 2001), along with "You With Us" (secondary slogan; to promote Cartoon Cartoon Fridays) in 1999 (until 2003). Powerhouse is widely considered the network's best era alongside the CN City era, due to its sheer variety of high-quality programming, and was one of their longest-lasting eras.

The Powerhouse era was used by Cartoon Network Europe from 1999 to 2002. Latin America also used this look from 1999 to January 1, 2005. In Asia and Australia, this era lasted from August 22, 1999 until October 1, 2005. In Japan, this era aired all the way until January 1, 2006.

Bumpers
The era was named after the Raymond Scott composition "Powerhouse", which was the musical theme for most bumpers and graphical elements of this period. However, on January 20, 2003, the Powerhouse music was removed from the bumpers and replaced with a series of generic fanfares and library themes (except for the Robot Jones, Codename: Kids Next Door bumpers, the turkey one for the "Coming Up Next" bumper and on the later weekends, when the Powerhouse music was used for Coming Up Next bumpers). Also, the yellow, green and dark blue/black backgrounds for the bumpers were removed in 2003 (with the strange exceptions of the "Coming Up Next" bumpers until May 2003), leaving only the blue and purple backgrounds still in use until 2004.

The colors used for the Powerhouse branding referred to different time periods. Yellow was used for weekday mornings, green was used for weekday afternoons, blue was used for weekday evenings as well as all day long on the weekends, while dark blue/black was used for midnights and late night periods. Purple was used for action cartoons, orange was used for Halloween, brown was used for Thanksgiving, and white/light blue was used for Christmas. Red was originally the color used for midnights and late night periods until mid-to-late 1998, when the color was replaced with black/dark blue due to older TV sets not withstanding the color red way too much.

When the Powerhouse era was slightly updated in 2003, not only was the original music removed from the "We'll Be Right Back" and "Back to the Show" bumpers, but the green, yellow, and dark blue/black backgrounds of those bumpers were also removed, leaving the blue and purple backgrounds seen during those bumpers seen from 2003 to 2004. However the green and yellow backgrounds were not removed entirely from the network, as the "Coming Up Next" bumpers often contained the green and yellow backgrounds until May 2003. These continued to be mixed with the blue and purple "We'll Be Right Back" and "Back to the Show" bumpers until June 2004.

In the "We'll Be Right Back" and "Back to the Show" bumpers for many shows in evening time, primetime in weekdays and weekends, the era's announcers Hartman, Shearer, and Clark were replaced as announcers by CN characters, such as Bugs Bunny (voiced by Jeff Bergman), Dexter (voiced by Christine Cavanaugh), Ed (voiced by Matt Hill), Lu (voiced by Nancy Cartwright), Mike (voiced by Nika Futterman), Courage (voiced by Marty Grabstein) and Johnny Bravo (voiced by Jeff Bennett). Also, in the Powerpuff Girls-related bumpers, the voice of the narrator (voiced by Tom Kenny) was used instead. The bumpers with the characters as the announcers were used until 2003 when the Powerhouse bumpers were overhauled.

The Sylvester and Tweety Mysteries, Codename: Kids Next Door and Whatever Happened to... Robot Jones? were the last three shows to receive new Powerhouse bumpers in 2002. When Grim & Evil split and separated into The Grim Adventures of Billy and Mandy and Evil Con Carne in late 2003, the two series did not have their very own Powerhouse bumpers. They, Star Wars: Clone Wars, and Megas XLR, were the only original Cartoon Network series to not have their very own Powerhouse bumpers that aired during the commercials.

After Adult Swim signed off at 5:00am on June 14, 2004, Time Squad and Captain Planet were the final two shows to air under the Powerhouse era. At 6:00am, the City era debuted and The Powerpuff Girls was the first show to air under the City era. Also, when Toonami: Midnight Run aired or after Adult Swim signed off during that time, the dark blue/black "Coming Up Next" bumpers were also used.

Programming
With the transition from both the Checkerboard and Starburst eras to the Powerhouse era, the network slowly began to feature their original series more prominently. This eventually led to the classic animation programming block, Boomerang, being split off into its own network in April 2000, taking most of the classic Hanna-Barbera series with it. A total of 14 original series were produced during this era.

During this era several notable programming blocks were introduced including: Cartoon Network's Cartoon Theatre, a movie block that aired on CN from July 1998 to 2007; Cartoon Cartoon Fridays, a weekly programming block through which the network premiered new episodes of its original series; and Adult Swim, a late-night block aimed at a more mature audience that would become it's own channel and take over the entire night schedule in 2005 (despite still sharing channel space with Cartoon Network).

When the Friday-themed program blocks were not airing at any time of the week, The Grim Adventures of Billy and Mandy and Evil Con Carne episodes that first aired on Grim & Evil were the only episodes seen during the Powerhouse era's normal weekly and weekend programming.

CN Original Series

 * Space Ghost Coast to Coast​ (entered hiatus on December 17, 1999, restarted on May 7, 2001 and ended July 22, 2001, moved to Adult Swim on September 2, 2001)
 * Dexter's Laboratory​ (originally ended on December 10, 1999, restarted on November 16, 2001 and ended November 20, 2003)
 * Johnny Bravo
 * Cow and Chicken​ (ended July 24, 1999)
 * I Am Weasel (ended March 2, 2000)
 * The Powerpuff Girls (premiered November 18, 1998)
 * Ed, Edd n Eddy (premiered January 4, 1999)
 * Mike, Lu & Og (premiered November 12, 1999 and ended May 27, 2001)
 * Courage the Cowardly Dog (premiered November 12, 1999 and ended November 22, 2002)
 * Sheep in the Big City (premiered November 17, 2000 and ended April 7, 2002)
 * Time Squad (premiered June 8, 2001 and ended November 26, 2003)
 * Samurai Jack (premiered August 10, 2001)
 * Grim & Evil (premiered August 24, 2001 and ended October 31, 2003)
 * Whatever Happened to... Robot Jones? (premiered July 12, 2002 and ended November 14, 2003)
 * Codename: Kids Next Door (premiered December 6, 2002)
 * The Grim Adventures of Billy & Mandy (premiered June 13, 2003)
 * Evil Con Carne (premiered July 11, 2003)
 * Star Wars: Clone Wars (premiered November 7, 2003)
 * Megas XLR (premiered May 1, 2004)