This is the best sandbox style game I have ever played. Its difficulty settings are optional, so that the newbie can enjoy as much as the hardcore veteran player. The controls are excellently well made; this is a really cool, darker look at the superhero thing. The appropriateness of the game is actually kind of a moral choice; do you become evil, obtain powers of destruction that will probably kill civilians as you fight bad guys, spread discord in the city and suck the life out of people, or do you heal injured civilians, restore unity, and learn powers that heal you and stress accuracy and defense? Its ultimatly your choice whether to be the good guy or the bad guy, and if we are talking appropriatness for children, being the good guy yields gameplay very much like a wonderful superhero movie. You are a character named Cole who has mysteriously obtained the power to wield electricity as a weapon since a huge blast detonated and destroyed your city. You also gain the power to fall from any height without getting hurt, to do crazy parkour moves, and to shoot lightling in a kind of 3rd person shooter gameplay. Its a platformer, sandbox, collecting game, semi roleplay, game that does an excellent job. You may find yourself simply spending hours just running from building to building, admiring the indestructible lighting bolt of a man you are.
However, for those who choose to play as an evil character, the game becomes much darker and obviously loses all moral goodness by default. Its a cool choice for adults, and interesting for kids. But I knew a parent who would only let her kid play it if they played it as a good guy, and for younger kids, I understand that stance.
This game has mature language and a dark feel to it, but violence wise, if your the good guy, its really not that bad; the only thing you'll be killing is cloaked monsters that don't even bleed.