Tittle say everything, i want to check if you can use Hand of harm and Stunning strike in the same attack of course ill be spending the two ki points.

Also with that as a lvl 6 Way of Mercy monk if i could do the above would that proc in that same order?

Attack hits > spend a ki point for hand of harm and cause poison > use ki for stunning strike and enemy got disadvantage on the save (XD yes evil laugh)> then continue to plummet a stunned enemy.

Basis of question would be can more than 1 ki ability be used on the same attack?

Edit: Mistake on poisoned condition giving disadvantage on saves.

I would do as RAW dictate order since it would make sense, but also DM fiat since is strong combo.

A poisoned creature only has disadvantage on Attack rolls and Ability checks, not saving throws. 

So, yes, you can use both at once, but the poison wont affect the success of your SS 

The active player determines the order of operations, so if it’s your turn the. You would determine which happens in which order. However Kaboom is right, the poisoned condition won’t affect the saving throw for Stunning Strike.

Quote from Kaboom979 >>

A poisoned creature only has disadvantage on Attack rolls and Ability checks, not saving throws. 

So, yes, you can use both at once, but the poison wont affect the success of your SS 

 I stand corrected Kaboom is right so half of the post is null i shall edit