Very little. You won’t know you’re attacked but don’t die from it unless your ability states so (the scum guys know if they’re attacked), and no scum knows why an attack failed/didn’t work, but in vig’s case they will get a “your target did not die” (although if that’s because they are another scum, doc or healed is not known to the vig) as feedback. Other scums don’t get any feedback when something fails to go off (while arso can figure out who didn’t die as intended when they ignite they won’t get a list or anything from me, nor a reason, and anarchist bombs don’t give feedback when they go off).
Edit: Also if anybody needs confirmation on when the anarchist bombs go off, it’s Plant Bomb -> Day -> Night -> Day -> Night -> Dead
