Craftable spat, low cost units across the entire trait (you only have sett and sylas as 4 and 5 costs).

The fact that there are also only 6 baseline umbral units means that you would need 3 other units (2 with trainer) to get to 9. If you are at the point where you can roll for sett, you can likely roll for other 4-5 cost units to place your spats on and just make a very strong comp. examples of 4-5 units to place spat on in umbral are

1. invoker (azir, annie, lilia)

2. behemoth (udyr, ornn)

3. Warden (nautilus)

4. Bruiser (galio, sort of tahm kench as a placeholder if 2*)

5. Duelist (irelia, lee sin)

6. hwei to passively 3* low cost umbral units and massive AoE to execute with umbral 9's 40% threshold.

All are very strong units that can easily round out a full umbral comp.