Through a series of Leads and interrogations, you acquire a simple swap-bot from the Aether Pirates. You have a computer specialist (or yourself) reprogram the bot to do any number of things to the local Pirate Airship. You also add some shielding and weaponry to the bot, in the event you're found out.

You then send the bot on its way and it sabotages the airship, giving you a chance to rescue some hostages on board and/or some technology the Pirates had stolen. Yay! You Win! Pirates Lose! And all it took was a hacked robot to save/ruin the day.

...

Now, c'mon, that's a bit lame, isn't it? You just send the bot on its merry way and mission accomplished. There's a much more active and innovative way to go about this:

[b]You[/b] pilot the bot.

Rather than send the bot on its way, you take over the bot, control its flight, weapons, shields, stealth systems, etc. You then play the first part of the mission [i]as the bot[/i]. Think of it like the Kheldian shapeshifts: your main powers are turned off, in exchange for the powers of the new form. Your Martial Arts/Fire Bulwark [Tanker] loses all of his powers for those of the bot's: Auto Flight, chain guns, missiles, shock shield, magnetic shield, cloak, breach.

You then go through the instanced (or non-instanced) airship, avoiding discovery by its crew, while breaching the door with the hostages in it, then making your way to the main power, then detonating. You're then transferred back to your character back to the ground or at the entrance of the Airship, you bust through the failing ship, facepunching Pirates on the way, maybe you face off against the captain OR you avoid such a confrontation, make your way to the hostages, escort or otherwise extract them, and leave the ship before it crashes OR too many Pirates are on your tail and extraction becomes dangerous.

Which is better?

Such a system could have wide-reaching opportunities for CoT as a whole, but especially in the Mission Creator. This would allow you to tell stories without your character (or another's) being a part of it.

Imagine the President Marchand arc, where you go in the past to assassinate President Marchand of the Rouge Isles in order for Lord Recluse to take power. It always seemed awkward to be sent in the past to do such a thing when it could have wide time-wimey consequences. Instead, you could tell the story through the assassin that actually committed the act, in a flashback of sorts.

The issues:
-A player may not enjoy the powers given to the Other Role. The Pirates example is less, since it becomes a sort of stealth challenge, but playing a whole Arc as another character could be tasking. If the Other Role is a Gladiator (Brute) but you mostly enjoy ranged characters, it'd be annoying to be forced into another play style you're not big on. One solution could be to make the Other Role very powerful, but not so much that it's overpowered and feels like God Mode, but enough to counteract the issues with forcing another set of powers. Maybe you could give it some flexibility PCs don't have, like a totally free form selection of powers (without consequences of Tertiary Powers) (and I feel that free form selection of powers is a MUST for NPCs made for the mission creator). A well-crafted Other Role would also make it more enjoyable, but that's up to the creator of the Arc.
-I don't know how UE4 would handle shapeshifts or player transfers like this, but I'd be surprised if transformations were outside the range of UE4*

Thoughts?

I really feel like this feature would open up many possibilities for storytelling through Plots, Stories, and Arcs, inside and outside the Mission Creator.

*Note: KS update 28 mentions "monster play" as a form of PvP. This is where one character takes over a monster and pilots it while other players attempt to incapacitate or otherwise stop the monster's path of destruction. This indicates that such a system could exist in UE4, and that the Devs have thought of such a system, these aide to the feasibility of it.