The Astral Guardians sense that the Elixir has been used.
Chapter 10 Page 34
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The Astral Guardians sense that the Elixir has been used.
All 12 other Sector Guardians sense that Akiva has used the Elixir. 12 panels show each in their respective sector. Most look surprised, shocked even, or nervous, others look almost peaceful. Mathon in particular looks pleased, like they knew exactly what would happen the whole time.