There appears to be a 'ghosts' feature which is optional in non-hotseat multiplayer games. This will give the players some pseudo-heroes (ghosts) which they can only use when it is not their proper turn. These ghosts don’t directly interact with the real world like a proper hero does but seem to be able to scout, slow down enemy heroes and steal resources. Ghosts can battle with ghosts from other teams, but not 'real' stacks.
Fabrice said the idea was to kind of make it like hotseat mode, where you can look over the other player's shoulder while you're waiting for your turn. It sounds interesting and it should give players something to do while they're waiting for the other person to finish their turn. He also mentioned the simlutaenous turns mode again. He didn't give any new details but did re-confirm that it will be mainly used to speed up the early game.
Update: Sorry, it completely slipped my mind when I first wrote this, but Fabrice also spoke about another multiplayer mode - duel. He predicted these duel games would take about 15 minutes and would involve minimal adventure map interaction. The primary focus of the mode would be the player selecting some armies to have a tactical fight with the opponent.
I think this means all five promised multiplayer modes have been announced:
- 'Vanilla' multiplayer
- Hotseat
- Simultaenous turns
- Ghost mode
- Duel mode