Frozen monsters are unable to act, Fire resistance is increased by 1.5x Ice resistance.
The change to the monster's Fire Resistance is not displayed to prevent bugs, but it still takes effect.
In addition to other modifiers, the monster receives a bonus to its roll equal to 25 - (IceResistance-100)/10.
If you (the Player) are frozen and you do not act for a turn, then during that turn Pets and Guests attacks deal 0% Stats damage.