[LintMan]

I love that defenders can teleport/gateway into besieged castles... In my current game, I had a built a castle as a lone outpost on the other side of some oceans, but I had a hard time staffing it because it had virtually no resources. Some time later, Pangaea parked its 300+ unit army of massed centaurs and minotaurs on my poor 15-man castle and instantly battered down the gates.

So I teleported/gatewayed in:
4 Juggernauts
2 Elephants
1 Abomination
12 Mandragoras
6 Ghosts
22 Living Statues
and 2 fully equipped trampling SC's. (All these troops were being built up at a distant castle as part of a planned sneak attack on a different nation)

All arriving just in time to defend Pangaea's castle strom the next turn. Woot! That was a fun battle!