Spren Attack?

[Trusk'our he/him]

In RoW, Rlain teaches the humans that it is possible to use Stormlight and a specific Rhythm to make Lifespren encourage the growth of plants. But could more be done?

What if you had a bunch of Flamespren and a large ruby filled with Stormlight, then used a specific Rhythm to encourage them to start fires? Maybe not the most directly dangerous weapon, but it would be pretty interesting and could cause chaos amongst your enemies.

[Quantus he/him]

Probably.  In the case of the Lifespren, it encouraged them to take in stormlight and then sort of pollinate the plants with them.  If the flamespren can similarly be handed Investiture and then encouraged to deposit it in thematically appropriate places (ie kindling, etc) then it should work.  Im guessing the secret sauce is in finding the precise rhythm/Song that encourages/incites the specific target behavior in a given spren species.  

[Lighteyed Lieutenant he/him]

I can see some deviousness happening with painspren. Or ruin a collection of important letters with inkspren? Hold a gate or door with bindspren?

[Elite01]

Could you use a certain rhythm to make anger or other emotion Spren “deposit” that emotion to other people to get bootleg emotional allomancy? 
 

playing a certain rhythm to attract and interact with music spren would be interesting but I don’t know what effect it would have. 
 

doing something similar with wind spren to provide wind for a sail of a ship would be interesting.

it begs the question of how much can spren create/influence 

[Weaver of Shadows he/him]

If this is possible, deathspren and rotspren would have interesting attributes.