Where are T3 1* Cosmic Evo runes?

[DeathDealer-5301]

Looks like I'm out of these. Pressing and hold the icon tells me they drop from evolution events. Is that really the only way to get them?
Cosmic LOL doesn't say it drops them either.

[Yup]

Cosmic dungeons - Magus, Gunner, Warrior, etc.... -- they are cosmic talisman items, so the cosmic talisman dungeons drop them.

Many of the key-requiring frontier dungeons will drop them with varying frequency, although not any LOL or the daly/weekly.

[Azagthor]

Cosmic Talisman and Frozen Wasteland are the only two key dungeons that can drop the 1* T3s (afaik). Otherwise you'll need to get lucky in the Evolution Material Horde (and maybe Cache?) skull quest mission, or from Catalyst souls.

They're still pretty rare, and I'm not sure which of those two dungeons is the most efficient in terms of SoT/1*T3. Will likely come down to what other rewards or achievements you're looking to complete at the same time.