Ensure all structural elements (floor, window, ceiling, walls, door) are reinforced with gift boxes. Make sure to use the clock on the baby and the cat to transform them before the zombie attack.
The key to this level is strategic use of the clock and gift boxes to upgrade defenses and characters. Prioritize transforming the baby into a werewolf and the cat into a dog for strong combatants. Reinforce all parts of the house to withstand the zombie assault.