Tactics against Necromancers.

Tell me, what map is this, I've never seen 20k liches:)?

There are quite a few such maps. Any L or XL map that features legions of neutrals can bring a necro player with the Cloak of the Undead King a very large number of liches.

I remember one map where the stacks I was accumulating liches into got nullified (this is a program bug that occurs when processing large numbers). There were about 500k liches! I didn't notice this glitch, and then at one point I look - and they're already "0"... Or rather, "minus" :) I had to go back and replay... VDV_forever should remember that map well... He showed himself heroically there :)