Thank you for sharing your work, and for requesting a review from me. This review is only my own opinion and is constructed to help you as well as I know how.
I like this take on people with powers appearing due to some unknown event. It makes me think of George R. R. Martin’s Wild Cards series of stories. It looks like the beginning of a larger work, so I won’t dwell much on the gaps in the plot as I assume they will be filled in later on, though I will mention them just to be sure.
Your story seems to really begin with the Event, which you leave as an unknown. There is a six-month gap in time between the prologue and Chapter 1, during which the reader is left wondering what happened in the intervening time. I hope this is filled in later on, possibly through flashbacks.
One quibble here: Why would a game cost three hundred dollars? What sort of game is it? Also, Eric turns his pockets inside out for loose change. Was he really hoping that the loose change in his pockets would add up to three hundred dollars?
Eric and Gareth find themselves in the park, helping the people (presumably without powers) defend themselves from the Reapers. Why would Eric notice the Reapers sneaking into the crowd, but no one in the crowd notices? That’s a little hard to believe, unless the Reapers are dressed exactly like the people in the crowd, in which case, how did Eric notice them? Is that another power? Eric seems to be exploring another power he has – leadership, which for a fifteen-year-old boy is pretty impressive. Are the adults in the crowd really going to follow direction from someone this young? Eric carries out some feats of strength throughout the park scene, but no one seems to notice until he does his mind-blast thing, which marks him as a “freak.” Why didn’t the crowd notice his abilities when he jumped off the building, or the statue? Also, the crowd seemed ready to keep fighting Eric even after his display of power knocked them all down. Wouldn’t they be scared off? I know I would be. The TV on the building seems to be significant in some way, but it only functioned as a plot device to connect Eric with the other people with powers. I was expecting more from it. Maybe in future chapters?
The quarantine sets up a good setting for this story, where people are trapped and have to deal with each other, and with whatever lurking evil may have shown up. I would have liked to have known more about the quarantine, and how it’s being enforced. If you are trying to express the isolation of the inhabitants of this quarantined city, then you did it well. Is there anything else happening outside the quarantine?
Another quibble: you describe a massive structure in the city that didn’t exist before the Event. Apparently, they built it in six months, with no outside help or contractors. If it was built using powers, or if it has always existed, that should be explored as well.
You keep things moving quickly in this story, and that’s good. Just don’t leave out important details, or the story might not make sense.
I enjoyed seeing Eric’s character develop, and it happens quickly. He seems to embody attributes of both a fifteen-year-old, and an adult, like someone who was forced by circumstance to grow up too fast. I like this development, and I think you should continue to run with it. However, I think you should have done more with Mum and Lewis. They are Eric’s family, and they would have figured prominently into his character. They would answer a lot of questions about who Eric is.
As I already mentioned, I think you should revisit the behavior of the crowd in the park, because it’s not quite believable. How would the other characters behave? I thought that “mini-hulk” caved a bit too quickly to let Eric and his family in to see the leader. I think another plot development would have been handy to nudge things in this direction. Think about the nature of each character, and how they would be inclined to respond to a situation. Their actions have to make sense.
You did a pretty good job with the setting. I got a visual of rooftops of dilapidated buildings, and a ruined park. Just remember to use all of the senses, such as smell or touch.
Good job with the dialog. It reads naturally, like people speak. Nitpick: at one point Eric says, “I’m not going to take your bloody money.” The fact that they are talking about money in dollar amounts tells me that the setting is in North America, or possibly Australia. I’ve never heard Americans or Canadians say “bloody.” Australians might, but other idioms of Australian speech are missing from the dialog. Of course, if this city is entirely made up, then is isn’t an issue; you can have your characters speak in any way you want. Just remember the readers, and what might make the story feel authentic to them.
For the most part, there are no grammar issues. Here is what I noticed:
I swiveled my head to the other side of the street,
"Whoa, easy there tiger," the old man said soothingly
When one character addresses another, separate with a comma: “…easy there, tiger,”
“Guessing what was about to happen, I yelled, "Oh, NO!" and was about to stuff the sphere back into its box, but before I could, everything disappeared in a flash of blinding blue light.
Run-on sentence. I recommend splitting it between “box” and “but”
It is a massive building that takes up at least a block, is fifteen storeys high at a minimum
I didn’t notice any other grammar issues.
I thought this was a good start to a fantasy story, and you should keep at it. Just remember to maintain continuity of the plot, and to have your characters behave as they should. In fantasy you have a lot of license to make things up, but always keep the story's authenticity in mind. It helps with the suspension of disbelief, which is the whole point of writing fiction, isn’t it? Keep at it, and you might turn out a compelling fantasy novel.