Just made an update to a spell I made based off of my experience playing Pathfinder Wrath of the Righteous - Sirocco. It's a desert themed spell and I wanted to keep most of the core features of the spell, but DnD-5e-ify it a bit.

Sirocco

Three topics that I think are worth raising:

• Is the wording on the spell clear? If not how should I clarify what is happening?
• Is this 6th level spell balanced against other spells of its type and level? If not, what changes would you make to it?
• Is this spell going to be a nightmare to DM against, given how many rolls a single monster might need to make? And if so, is there a way to mitigate that?

My initial thoughts on the last two questions:

• Surprise surprise, I do not believe it is unbalanced. Comparing to things like Wall of Thorns, or Cloudkill (5th level), Blade Barrier, etc. First and most importantly, the damage is very low. Passing that DEX save not only halves that low damage but also excludes you from any other effect of the spell that round. Importantly, the spell does not create difficult terrain, so a character that passes their DEX save can likely skedaddle out with a dash action and be fine (this cylinder/the location of the damage is not moveable unlike call lightning or moonbeam). Next, failing a DEX save does make you have to pass a STR save or else fall prone, so that's where some of the utility starts to come into play, otherwise the spell would just be a bad spell. But plenty of spells make you pass a save OR take way more damage AS WELL AS fall prone such as Destructive Wave. That spell does it for the price of one save, not two. Then, the last effect I think would rarely ever happen, but basically inflicts a level of exhaustion on anyone that tries to stand or move after failing the STR save - but only in exchange for a failed CON save. Importantly, you could simply stay prone, maybe even cast spells, and you would not become exhausted. In summary, in the unlikely event that a monster fails 3 saves in a row and try to move, they would take 4d6 fire damage (maybe some bludgeoning if they can fly), become prone, and gain a level of exhaustion. Or they could simply take the damage and become prone but either pass their CON save or not try and move and basically either escape the spell or use ranged attacks/spells with relatively little issue. In summary, I think that if anything this spell might lead to a few disappointments for my players because they will see the exhaustion and get excited but it might get really hard to get to the point where they're inflicting 1, 2, 3 levels of exhaustion on enough monsters. So a buff might be in order ;) 
• This is the kicker. There's probably too many saves here. A potential of 3 saves per monster per round for a 40ft diameter circle. That's 18 saves per round for 6 creatures if they fail two of them. One idea, which is something I just saw in Destructive Wave, is to make the damage based on CON (or STR) and not DEX and basically say "if you fail the check to stand up/move then you gain exhaustion". That might also remedy my above point where the fun parts of the spell might be locked behind too many saves.

Thoughts? Concerns? Debate!

The link doesn't work for me, is this currently private homebrew? Might need to just post the text.

Woops! Try now