D&D 5E Giant Boulder vs. Immovable Rod

[MarkB]

Which instantly shatters. Rocks fly everywhere and the DC is double and damage is tripled. BABHAHAHA

Either that, or the rod ricochets, slams into a PC's chest, and re-activates in the process, holding them pinned in place.

 

[Umbran]

Great math here... here's a slightly different approach.
The giant 300k lb boulder hits the immovable rod, which resists with a force of up 8,000 lbs at 1G (32 ft/sec ish) before breaking. I'm assuming gravitational acceleration since it's not specified.

Um... 1G is not a speed. It is an acceleration (32 ft/s^2). And the boulder only accelerates at 1g if it falls straight down.

Which, you know, having a 15' square piece of ceiling, weighing 300,000 lbs, just fall straight down and squish the party would be a very effective trap.

By the way - 300,000 pounds is roughly equivalent to two Space Shuttles, 2/3 of the Statue of Liberty, or one large adult blue whale. Just drop a whale on them, and be done with it...

Which leads us to consider, what's holding that monster back from rolling at all?

 

[Xetheral]

Um... 1G is not a speed. It is an acceleration (32 ft/s^2). And the boulder only accelerates at 1g if it falls straight down.

Which, you know, having a 15' square piece of ceiling, weighing 300,000 lbs, just fall straight down and squish the party would be a very effective trap.

By the way - 300,000 pounds is roughly equivalent to two Space Shuttles, 2/3 of the Statue of Liberty, or one large adult blue whale. Just drop a whale on them, and be done with it...

Which leads us to consider, what's holding that monster back from rolling at all?

A bowl of petunias?

 

[Umbran]

A bowl of petunias?

Both it and the whale do not so much fly as plummet.

 

[FireLance]

Both it and the whale do not so much fly as plummet.

Unless you can deliberately fail your attack roll against the ground. Come to think of it, if you close your eyes, shouldn't you get Disadvantage from the Blinded Condition?

 

[MarkB]

Unless you can deliberately fail your attack roll against the ground. Come to think of it, if you close your eyes, shouldn't you get Disadvantage from the Blinded Condition?

That would work against the ground, though it's worth noting that the effect would be cancelled out if you were aiming for the Ravenous Bugblatter Beast of Traal.