Alex Mercer has become a monster in "Prototype," and he wants to find out how and why.

That's the setup for this open-world game – the second this year, after the PS3-exclusive "Infamous," to put players in the shoes of someone who never asked for superpowers. But Mercer makes no pretense of being nice – there aren't any of the moral choices that "Infamous" protagonist Cole McGrath was given.

Mercer wakes up in a Manhattan morgue with a chest full of bullet wounds and no memories. But he soon finds that he can consume humans, copy their shapes and absorb their memories. He also has enough strength to lift and throw a car, and the ability to run up the sides of skyscrapers.

After sifting a hint from an early victim's mind, Mercer learns that he has a sister. With her help, he starts looking for clues to his disturbing transformation – and to the shadowy military group, Blackwatch, that begins taking over the city just as mutants infected by a strange virus start overrunning the streets.

Much of the story is presented as a flashback, as told by Mercer to a mysterious confidant nearly three weeks after the start of the game. The plot is interesting enough, but it's told in a herky-jerky way that makes it tough to maintain any narrative momentum.

One neat storytelling device is the memories of the people Mercer consumes. Certain targets are marked as part of the Web of Intrigue, a chart of plot points made up of tidbits of information relating to the plot at large. Absorbing them gives Mercer new pieces of the big puzzle.

"Prototype" is far more gory and violent than "Infamous"; Mercer's powers aren't neat and tidy, and he's not concerned with sparing innocent life. In fact, consuming civilians is often the only handy way to refill Mercer's health when he's in a tight spot, though soldiers and mutants tend to restore more.

Absorption and imitation are just the tip of Mercer's shape-shifting iceberg. New abilities are unlocked as Mercer progresses through story missions, and he can purchase upgrades and new powers with the evolution points generously doled out for defeating foes and completing story missions and side challenges.

Mercer's mobility and diverse combat powers make rampaging through the city a blast, but there are some control issues that make finer movements a pain.

PICKS AND PANS

RUNE FACTORY FRONTIER

3 stars

An offshoot of the farming-RPG series "Harvest Moon," the "Rune Factory" games mix a bit of combat in with all the plowing and planting. "Rune Factory Frontier" continues the agricultural adventures of Raguna as he arrives in a new town with a fresh row to hoe.

The game's a pretty mellow experience centered on day-to-day tasks and Raguna's relationships with his neighbors, though there is a story line to follow.

Raguna plants seeds in his fields and waits for the crops to mature before harvesting and shipping them off to be sold. Some crops grow best in certain seasons, and most take different amounts of time to mature. Much of the field is littered with debris at first, and special tools are needed to clear it, though it's not made clear where to find them.

Raguna can buy extensions for his house, such as a forge to make tools. He can capture the small, glowing Runey spirits that inhabit the land and release them to influence his fields or produce miracles. Apart from farming and wandering the town, there's also a floating, whale-shaped island above the town whose interior is a deep dungeon. Raguna can befriend and domesticate the monsters he battles there for use as livestock, and will find plenty of items along the way.

Nintendo Wii; $49.99 • Age rating: 10-plus

SINS OF A SOLAR EMPIRE: ENTRENCHMENT

3 1/2 stars

"Sins of a Solar Empire" was fantastic when it launched, though it did have a heavy emphasis on offense. The game's first mini-expansion, "Entrenchment," beefs up players' defensive options considerably, introduces a host of new features and improves the artificial intelligence.

Defensive upgrades have been moved to their own research trees, and some of the gaps in the offense-oriented technology trees have been filled with new abilities. Along with improvements to defenses, each culture can lay down fields of space mines and field units capable of cracking a fortress world.

But the most obvious new features are the starbases, incredibly expensive structures that, when upgraded beyond their vulnerable initial forms, can hold their own against entire fleets. These bases can be built anywhere, allowing players to create a foothold in enemy territory or hold onto previously uncontrollable areas such as stars and gas giants.

Each culture has a different kind of base with unique upgrades that are in line with their play styles.

Other additions include units designed to counter hardened defenses and smaller tweaks such as the new quick start option, which allows players to begin with a few extra structures that are typically built first thing. Not shabby for a $10 download.

PC (ImpulseDriven.com download); $9.95 Age rating: Teen

– Justin Hoeger