There Was Time for a Ritual
'As you move down the corridor, a strange sensation comes over you, and you realise that the very ground you are walking on is starting to tremble. The tremble turns to shaking, a mighty rumbling comes from every direction, and you realise that the whole corridor is starting to collapse around you! Small rocks fall first, but as the shaking gets worse larger stones begin to fall, as you dodge and dive to escape the rockfalls, which threaten the very integrity of the cavern you are in.
'Make dexterity saving throws.'
'Okay, I cast Guidance first.
'You don't have time to cast Guidance.'
'But you've been talking for ages.'