Story arcs will be short, narrative events ambiented in the Chicken Invaders Universe.
Gameplay-wise they will be a string of time-limited quests, divided into assignments (required and optional), each having a reward, with the final quest having the main item.
They will appear in the mailbox, with a red color and this 
symbol.
Upon clicked, they will bring you to the prologue and the first quest. When the quest is complete, a greyed out “Continue” button will become available, and that will bring you to the next page, the next chapter. It will continue like this until the final chapter, that, upon completition, will disappear from the message board.
Here’s an example of what a prologue could be:
Prologue: Roll Call from the Awaken World
The last thing your remember is the sound of a huge mechanical beast finally shredding into pieces, as you park your spacecraft in the orbit of a small terran world.
“Ariandel (your AI), remind me to never do the Moronic Challenge again, that was such a big waste of time, and while you’re here, please dismount the Moron Railgun, replace it with the Utensil Poker”
"Reminder set… Dismounting Moron Railgun… Mounting Utensil Poker… All commands executed.
“Good.”
Before you even realize, you fall asleep, sat on your pilot chair. However your sleep doesn’t last long.
Incoming Call! Emitter: UHF
Your AI screams this 3 times, before you finally wake to its sounds and the flashing green light on your communication device. You respond to the call.
“Recruit (your player number), Callsign (Your callsign), (a random numeber from 1 to 100) th (a random noun that fits) wing, responding from the (your constellation) Constellation.”
Recruit, your presence is requested at the nearest Heroware possible, we can’t share more details, make haste. General Jackson, out.
The call ends abruptly as it started.
“Ariandel, check fuel stored.”
“We have… 584 units of fuel”
“That should be plenty enough.”
To the sounds of your engines starting, you set to reach the nearest Heroware, not knowing what will you have to endure.
Quest:
(Required) Reach an Heroware. Reward: 100 keys.
From this point, I don’t know. These events could have unique items, only obtainable by completing the event. If iA wants some DlCs for this game they could expand upon this and make big story packs.