This is a nice trigger for letting minions know that their summoner has died. Creatures don't react to HPLT(1), nor to General(DEAD), nor to overrides for the Died() and Die() triggers, and they refuse to count death in CD_STATE_NOTVALID. But if you ask them whether their summoner doesn't have hit points above zero, this they recognize...
I'm putting up this little poem for those who want to delve into death. Without minions your only option would be to use a contingency, and that's going to give you a message - it might - and would interfere and be rejected by other contingencies with the same condition that might be on a character.