1: Will magic users be able to effect the geography of the world?
2: Will magic users be able to play with physics in any way? As in gravity say?
3: If so, (after boats are implemented I would assume) would fortresses in the middle of the ocean be possible? If able, a magician could part the ocean for long enough to build the framework, for example.
4: Also if so, would floating fortresses be possible in any form?
5: In adventure mode, will flying ships be implemented in anyway, or even be possible? I just really want to descend on an unsuspecting town from the sky to raid and pillage.
1. Indirectly as a minimum, i.e. summoning/performing rituals that result in changes/releasing powerful entities that affect changes, etc/changing cosmic power balances that result in a different sphere dominating. Probably not in the first Myth & Magic release, though.
2. Sounds reasonable. Flying/levitation spells are common enough in fantasy.
3. In principle, but hard in practice, if by "fortress" you mean a fortress mode one rather than an adventure mode one. It's a bit tricky to get a starting team with a wagon to keep afloat long enough for their wizard to do the stuff required (but starting scenarios may change things, especially when boats are around).
4. Floating and flying fortresses are probably going to be possible, although you may have to start from a pre existing "platform", such as a flying/floating island. After all, it's something that appears in fantasy a fair bit. Flying terrain is planned to be available for highly magical worlds, I think.
5. Sounds very reasonable eventually. It would have to be a magic world, or you'd bend the 1400:ish cutoff quite a bit (Jules Verne:esque, at a minimum, as a "ship" sort of implies a heavier than air vessel, rather than a balloon [although a zeppelin might work]).