Yeah it would be an air fight. As for what happens after, I'd imagine the attacking fleet would remain hovering, though in a very diminished state. It would be up to the attacker at this point to decide if he wants to stil attack or would rather keep going.
That does bring up another idea though: the ability to move fleets to systems instead of planets. In the example above the player could move his now-diminished fleet to a nearby system while he sends another reinforcement fleet to the same system. This would favor attackers.
Speaking of that, dfsf I think you do have valid concerns but I don't agree that the current system "isn't broken". Things are stale, and I think there's an opportunity for improvement that could make things less stale if we can just figure out the details. IC's attacking is fun, but it is not perfect by any means. I think part of the problem with this game is that everything is so planet-focused when things can and perhaps should be happening outside of the planet.
An improvement on my original post here: What if instead of being able to detect enemy fleets over your planet by default, you could detect any fleets in your system but only through a special op, as twosidedeath mentions. So the example would then be:
Player_A sends a fleet to Player_B's planet 3 in system 1:2, and things work how they currently do.
Anybody in system 1:2, regardless of family, can cast a spell (if they have it) to see if what fleets are in their system. They would see Player_A's fleet.
Anybody who has this information can attack Player_A's fleet.
If Player_A has his fleet attacked, he can move it to another system. Whoever attacked him wouldn't know whether this is a complete recall or if Player_A just moved it 1 tick away. Meanwhile, Player_A can send in a replenishing fleet and then merge it with his original fleet. Perhaps even as a counter-balance, Player_A would be able to cast a temporary cloaking spell on his fleet (if he has it).
What I'm suggesting is essentially the introduction of war on a system level instead of just a planet level. It give systems a much higher purpose in the game, and allowing fleets to go to systems instead of just planets would allow for some very creative (and possibly sneaky) war planning. On top of all that, families on the defense would be able to help each other out more than they currently are able to.
Better for attackers, better for defenders, and the current stale formula that everybody follows is turned on its head.
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