In 1.18, hostile mobs are supossed to spawn only at light level 0, however, it seems like Pillagers can still spawn at light level 7.
I ve found It in both pillager outpost spawning, and in Pillager patrol spawning.
A very easy way to reproduce is to light up around a pillager outpost with redstone torches, since they emit 7 light levels.
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We're tracking this issue in MC-154090, so this ticket is being resolved and linked as a duplicate.
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