[Reference] Powers of the C'tan (All)

Pick a visible enemy unit within 24" of the C'tan Shard and roll a D6 (you can only pick a CHARACTER if it has 10 or more Wounds and/or it is the closest enemy model to the C'tan Shard). Add 1 to the result if the C'tan Shard using this power is a Tesseract Vault. On a 4+ the chosen unit suffers D3 mortal wounds, then Roll a D6 for every other enemy unit that is within 3" of the chosen enemy unit. On a 4+ the unit being rolled for suffers a mortal wound.

Roll a D6. On a 2+ the closest visible enemy unit within 24" of the C'tan Shard suffers D3 mortal wounds. On a 6, it suffers D6 mortal wounds instead. If the C'tan Shard using this power is a Tesseract Vault, the unit suffers D6 mortal wounds on the roll of a 5+ instead.

Pick a visible enemy unit within 18" of the C'tan Shard and roll a D6, adding 1 to the result if the C'tan Shard using this power is a Tesseract Vault. If the result exceeds the highest Wounds characteristic in the unit, one model from that unit, chosen by the controlling player, is slain. An unmodified roll of 1 will always fail.

Pick a visible enemy unit within 24" of the C'tan Shard and roll a D6 for each model in that unit. Add 1 to the roll if the C'tan Shard using this power is a Tesseract Vault. For each result of a 6+ that unit suffers a mortal wound.

Roll a D6 for each enemy unit within 9" of the C'tan Shard. Add 1 to the roll if the C'tan Shard using this power is a Tesseract Vault. On a 4+ the unit being rolled for suffers D3 mortal wounds.

Pick up to three different enemy units that are within 18" of the C'tan Shard. Roll a D6 for each, subtracting 1 from the result if the C'tan Shard using this power is a Tesseract Vault. If the result is less than the number of models in that unit, the unit suffers D3 mortal wounds. An unmodified roll of 6 will always fail.