If I roll a crit on a sleeping target with assassinate, do I roll 4x dice or is it multiplicative and I roll 8x? What happens to their body when I hit?
— Uriah Belletto (@DarkSlayerKi) April 13, 2018
Funny rules loophole: if you roll crit on a sleeping target with assassinate, you roll all of the dice you have. However, killing a sleeping person makes you a real turd, when you think about it (see the Player's Handbook for discussions on turds). #wrongDnD #fakeJeremy https://t.co/bsUUW3GztG
— spoilers swag (@katewelchhhh) April 13, 2018
For those who might be wondering honestly about those rules interactions: multiple circumstances providing a critical hit do not stack to provide a more powerful crit. All critical hits follow the same rule, roll the dice twice. Or as D.M. C.P. says ““All dice, roll twice. But leave the bonus alone-us.”