TAMPA — Muscle-powered rings of light shooting up the 31 stories of the "Beer Can Building."A herd of shaggy horse-dancers.Underwater lights that change with the movement of the people walking by above.These are some of the seven downtown art installations the city is sponsoring next Feb. 20-21 as part of its "Lights on Tampa" public art program."Bigger and better," Mayor Bob Buckhorn said in announcing the lineup for what he called "a signature festival for Tampa."Since it began in 2006, Lights on Tampa has seen the private investment of more than $2.5 million in permanent illuminated art. In 2012, the program worked with Tampa Electric to light up four downtown bridges before the Republican National Convention. The 2015 lineup includes:• Sky Striker by Traction Architecture of Tampa. The installation is aimed at turning Rivergate Tower, also known as the "Beer Can Building," into a larger-than-life carnival game. An old-fashioned "high striker" machine will be set up in Kiley Garden at the foot of the tower, but when contestants use a mallet to test their strength, rings of colored light will race up the outside of the 31-story tower to display the power of their strike.• HEARD, FL, by Chicago sculptor and performance artist Nick Cave (not the punk and alt-rocker from Nick Cave and the Bad Seeds). Cave will choreograph a herd of 30 dancers in near life-sized horse costumes at Curtis Hixon Waterfront Park. To see a version of the performance staged in New York's Grand Central Station, visit creativetime.org/projects/heard-ny• Glowing River by Wannemacher Jensen Architects of St. Petersburg. This underwater installation will be installed along the new $8.8 million section of the Riverwalk that is expected to open in late December or January. A string of motion detectors along the Riverwalk will trigger changes in the color of the lights as pedestrians walk by, or, if they wish, double back to create their own patterns of light. The underwater lights also are expected to attract fish and other aquatic life.• Recurrence by Luftwerk of Chicago. A grid of rhythmically changing lights installed in Kiley Garden will be designed to evoke the tidal flow of the Hillsborough River and mirror the garden's design and proportions, which are based on a mathematical formula known as the Fibonacci sequence.• Urban Pixels by The Urban Conga of Tampa, a nonprofit group that brought an outdoor hot pink ping-pong table to Lykes Gaslight Square. The group will set up Urban Pixels as a series of lighted shapes that can be moved around to create lawn furniture or other forms.• UpLit in the northwestern corner of Kiley Garden. This project will invite poets, writers and lovers of the written word, professional or not, to submit a phrase capturing "how we live now and what that means," officials say. There's no cash prize, but a panel of judges led by Tampa novelist Tim Dorsey will select a phrase to be temporarily put in lights on what the city describes as a "vintage rooftop-style sign." To submit a phrase, visit tampagov.net/UpLit. Entries should be no more than 75 characters, including punctuation. The deadline is Oct. 24. A winner will be notified in November.• Shadow Plays, featuring interactive music and dance, at Curtis Hixon Waterfront Park.