In my first Skype battle I fielded Nurgle daemons against Kraken's Tyrannids. I experimented with a Giant Chaos Spawn as I loved the look of all the random rolls and it was indeed great fun to use.
Next on my list to show you are the characters in the Second Law warband, starting with a Biologus Putrifier. He's usually my warlord so that the Daemon Prince can fly forwards and not worry about giving up Slay the Warlord. I usually give him the Arch Contaminator trait to maximise the effects of the Plague Marine squad acting as his bodyguard and the Foul Blightspawn who generally runs alongside him. I affectionately call him Maxwell.