Dark sphere

[Alexzang, etherium envoy]

Regarding {dark sphere} because it doesn't technically target according to the rulings, can you sac it at say an opponents upkeep, and later on choose what to prevent, or does it have to Be done just before "a source of your choice" WOULD deal damage

[Kaleo42]

You need to choose a source at that time. You could pick a creature or something long before it does damage if you wanted.

[Alexzang, etherium envoy]

Awesome thanks