The Tavern

Specifically, the ability to fling volleys of spines similar to the ability used by manticores, with whatever adjustments deemed necessary for balance

Thoughts?

There aren't a lot of mutations, either the random kind or innate species mutations, that grant active abilities, and I'm not sure the devs think it's desirable to have too many.

A passive variant might be that you reflexively fling spines at attackers who attack you from a distance -- retaliation at range, which has the same basic idea without having to trigger abilities.

What are the goal and motivation of this proposal?

The spines mutation is pointless (no pun intended). Seems pretty obvious to me.

It would also work to remove spines since it overlaps with passive freeze almost completely and even with miasma radiation partially, with both of these being more distinct since freeze is tied to a facet that isn't just three tiers of more retaliatory damage and the other doesn't just apply damage.

Most of the demonspawn mutations are designed well enough to be beneficial to characters of various skill-sets, equipment and playstyle. Spines fail to do this by placing heavy restrictions on what armour you can wear while remaining useful. This leads to spines feeling ineffectual and leads to the player wanting "something more" from this seemingly useless mutation.

The above text has (at least partially) been obsoleted by a commit from June 23. How useful spines are after the change I have not experienced yet.
http://git.develz.org/?p=crawl.git;a=commitdiff;h=4e5d555478ae371f598e3c732bd85cef134c41ff

Even if this change makes spines more noticeable, the question remains, "Why do we need both spines and passive freeze?" Does retaliatory damage change how the player plays and does that make it interesting enough to hold its own facet?

Some of the same sentiments from this thread were brought up in my thread on demonspawn spines from earlier this year, though much of that might have been taken care of by this week's commit. That the commit notes compare the proc chance to the former ring mail's chance make the change seem dubious compared to the tests in the thread.
https://crawl.develz.org/tavern/viewtopic.php?f=8&t=11436

Spines are more useful against cold-resistant foes, at least. How much damage do each of the the mutations do?

spines are just a worse retaliatory headbutt, are not interesting at all, and help very little against anything that matter.

what we need is a really really fast hedgehog race with spines 3

imo it should be re-flavored as an aura of some sort

just so that the player's armor doesn't decrease damage

equipment disabling body mutations is dumb, even if it makes logical sense in-game