[Cainehill]

What I like to do with Tarrasques is ... Empower them a bit. Give them some water - haste & BoW. Fire : at least a minor fire shield. Air : missile shield and also flight, so your terrasque can kill _everything_. Nature, for extra regen; earth (once at 2, or using gems, summon earthpower for fatigue), etc, etc.

Give a terrasque two or three magic paths, then add on a ring of wizardry if you can, or whatnot, they can be brutal.