My question revolves around abilties such as Unshakable Faith and the Voidmaster's mastery abilities. They state that you re-roll all failed tests. Now does that mean you just re-roll once if you fail or re-roll until you don't fail?

Also on a side note, the explorator's special ability where he starts off with two common craftmanship bionics. Does that mean he can't take a mechadendrite because they are all considered good craftmanship normally?

1. Re-roll once, accepting the second result even if it's worse.
2. Unless the Explorator spends experience to upgrade them, no.