Plant growth + wall of thorns = 8 feet of movement per foot moved?

[Segev]

I see no reason these wouldn't stack, though the thorns at least only are five feet thick. Still, 40 feet of movement to get through that wall is impressive. I don't think these counts the same macar effect, but am open to arguments about that.

Could I be missing anything else?

[sithlordnergal]

Mmm, I don't know if it would work...similar effects tend not to stack. I.E. if you cast Web and Spike Growth in the same area, the Difficult Terrain doesn't stack. Though it could work...Personally I stick to Spike Growth + Plant Growth

[Corran]

I see no reason these wouldn't stack, though the thorns at least only are five feet thick. Still, 40 feet of movement to get through that wall is impressive. I don't think these counts the same macar effect, but am open to arguments about that.

Could I be missing anything else?

I could see one or two interpretations about them not stacking.

First one could be that plant growth specifies it affecting normal plants, and wall of thorns is not that (being created by a spell).

Another one, is that plant growth messes up with the density/structure of the plants so that it creates excatly a 4/1 loss of movement (so in theory -assuming there was a spell that offered a higher movement reduction- it could even be used to makes plants less thick), which means that it cannot affect the plants from wall of throrns in that aspect, as it is already thick and overgrown enough.

The most convincing one is that it's basically the same effect stacking, which is a no-go as per 5e rules. Why dont you think it's the same effect though?

Mmm, I don't know if it would work...similar effects tend not to stack. I.E. if you cast Web and Spike Growth in the same area, the Difficult Terrain doesn't stack. Though it could work...Personally I stick to Spike Growth + Plant Growth

Plant growth and slow is also cool.

[Segev]

I could see one or two interpretations about them not stacking.

First one could be that plant growth specifies it affecting normal plants, and wall of thorns is not that (being created by a spell).

Another one, is that plant growth messes up with the density/structure of the plants so that it creates excatly a 4/1 loss of movement (so in theory -assuming there was a spell that offered a higher movement reduction- it could even be used to makes plants less thick), which means that it cannot affect the plants from wall of throrns in that aspect, as it is already thick and overgrown enough.

You could theoretically cast plant growth first, and wall of thorns within the region second, which would actually be optimal for controlling movement as much as possible, I think. This would mean that plant growth is not affecting the thorns, but the thorns are springing up within the already-overgrown area.

The most convincing one is that it's basically the same effect stacking, which is a no-go as per 5e rules. Why dont you think it's the same effect though?

It isn't the same effect, though. Two different spells, neither of which is referencing a particular status or condition, just describing the effect each one has.

That said, I can see the "I mean, they're both thick plants" argument for "same effect," too.

Plant growth and slow is also cool.

Need a second caster for it, though. Not because of Concentration, but simply due to the spells not being on the same classes' lists.

[tiornys]

Need a second caster for it, though. Not because of Concentration, but simply due to the spells not being on the same classes' lists.

Bard gets both spells under Tasha's optional rules (and could use Magical Secrets to grab Slow if those additions aren't allowed). Land Druid (Arctic) gets both spells, as does an Archfey Warlock with the Mire the Mind invocation.