Communication from …

Custodian protocol 955-1 activated. Message follows: Attention, …. Your civilization is deemed to be compromised by <<ERROR: DATA BLOCK CORRUPTED>> influence. To contain the danger to other civilizations, we have activated compliance protocols. Refrain from all aggressive acts of war for a period of 20 standard years. If you fail to comply, war assets will be activated to enforce punishment protocols against your empire.

The command below will trigger the "Communication from …" event in Stellaris:

When this event fires, you can choose between the following option:

• That's not good...

Stellaris events fire in chains — one event leads to the next. Here is how Communication from … (fallen_machine_empire.61) connects.