Do you remember playing Pyke botlane before he was nerfed to hell? or Pyke midlane or Pyke toplane or Pyke every role lane?

Meet Kalista. She is pre-nerf Pyke but it's ranged version. With your co-operated pokes, you'll deal massive 14% max hp damage at LVL 1. With your level 2/4 Q and smart trades, you'll get those kills like collecting rare pokemon cards.

One major problem you need to know about her is that: You can not Roam. At least not actively; only when your adc is dead/away/safe farming without any enemy. Otherwise your whole kit and gameplan is meant to be centered around your ADC, Like a submissive Lulu chasing his ADC everywhere. So until your laning phase is over, try not to get too curious on the rift.

So your ADC just got afk? Or it's a troll? And you are already bound with your ADC, so your ult is now completely USELESS. You might ask and think about what the hell you can do in this situation.

Answer is... Nothing. You don't have to do anything different than what you were already doing, just play around your jungle and other lanes. You already have massive damage peel as Kalista, so be useful. In a 4v5 scenario, you are the best your team can get when your adc is troll. You don't want a team of 3 damage dealers and 1 low damage support.

I get it, you might be confused. why would i let my adc get thrown to the enemy?
The answer relies on the way you use your ult. It's not only an engage skill, but really good when you are chasing the enemy, or even saving your adc even if you die in case of ganks or in the teamfights.

I do not recommend trying this on Solo Queue if you dont have a premade ADC, if you don't care and play anyway; make sure to inform your adc what you are playing, since some of them get confused and try to play as support ( first-hand experience, IQ of league community is varied on a wide spectrum after all ).