"Why don't you dismiss that freezing aura of yours first?" Renia suggests... but it's pretty obvious how likely she thinks that is to happen, since she segues directly into her Riven Hourglass stance, and begins throwing magic at him.
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Renia's dipping into her time pool to prepare her new Polar Ray, then throwing that and her split scorching ray at Sepulchrus.
"Polar Ray Attack (ranged touch)" - (1d20+14)[22]
"Polar Ray Damage (switched to Sonic)" - (16d6)[58]
"Scorching Ray #1 Attack Roll" - (1d20+14)[19]
"Scorching Ray #1 Damage Roll" - (4d6)[17]
"Scorching Ray #2 Attack Roll" - (1d20+14)[17]
"Scorching Ray #2 Damage Roll" - (4d6)[12]
"Scorching Ray #3 Attack Roll" - (1d20+14)[21]
"Scorching Ray #3 Damage Roll" - (4d6)[15]
"Scorching Ray #4 Attack Roll" - (1d20+14)[21]
"Scorching Ray #4 Damage Roll" - (4d6)[13]
If Sepulchrus counts as evil, half of all the damage above will be Divine damage instead of elemental.