Cyber Brain (4e Future Technique)
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Overcharge: When you start your turn you can roll a d20.
♦10+: The power bonus increases to +8 until the end of the encounter. In addition, if the encounter is a skill challenge and you roll a natural 20, it counts as two successes towards the challenge.
♦9 or less: Until the end of the encounter, whenever you make one of the skill checks listed above, the DM makes a secret die roll. If the die roll result is an even number, the +4 power bonus becomes a -8 penalty instead.