The best replacement for moat is mote.

The best alternatives to moat are rated as following:
★★★★★  mote
★★  ditch
★  wmw
★  magic tower
  motte

Your alternative for moat is not listed? Suggest!
Speaking about moat, one probably shouldn't forget about drawbridge.

Other search terms related to moat and their ratings are:
★★★★★ drawbridge
★ gazza
no castle
You have in mind a companion for moat and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of moat in all years. Click on graph for more.
moat
mote
ditch