shouldn't stack probably. but how about this instead:
tireless march costs 0 mana but takes 2 hp per move for all units in the stack.
so you can cast it on your stack of heroes and get 7 moves, but they'll take 14 damage per turn (assuming they use all seven moves eachvturn)
this would be especially painful for regular units. so it might be a good wau to get your champs around the map but not so good for armies.
