I have cast Blink on a previous turn and I am facing a solid wall with at least 5 feet of empty space on both sides. During my turn I ready an action with the following trigger: "When I enter the ethereal plane, I move 10 feet forward."
When my turn ends, I enter the ethereal plane and use my reaction to execute my readied move which lets me pass through the wall so that I end up on the other side.
I can now no longer see the space I vanished from, but I can see a space on the other side of the wall I passed through which is within 10 feet of the space I vanished from.
- I roll 11 or higher on the end of turn D20 roll for Blink
- I can execute a readied move while in the ethereal plane. (as per this Q&A)
- I can move through walls while I am moving in the ethereal plane. (as per the same Q&A)
Blink says the following on returning to the material plane:
you return to an unoccupied space of your choice that you can see within 10 feet of the space you vanished from.
Questions to answer:
When my next turn starts can I reappear on my original side of the wall even though I can't see it anymore?
Conversely, can I reappear on the other side of the wall since I can see it and it is within 10 feet of my starting location?