1. Give us the steps to reproduce the bug:

When the ETB effect of Stalwart Realmwarden is triggered multiple times by Starfield Vocalist or Elesh Norn, Mother of Machines the second ETB doesn't stack the "the next noncreature spell costs 2 more to cast" effect. It used to work fine, but it no longer stacks properly.

1.   Note which platform you’re using (PC, Steam, Mac, Android, or iOS): PC, Android
   

2.   Enter the actual results you’re experiencing: ETB only stacks 1 ETB effect (not the expected 2x)
   

3.   Enter the expected results of the feature: ETB stacks 2 times (the next noncreature spell will cost a total of 4 [*2+2] more to cast)
   

4.   Add any relevant screenshots/videos: no
   

5.   If you found a workaround, please add workaround steps: no