I only mention this because it seems that not too long ago a similar bug was fixed to this same effect. But basically, when Sona has her powercord up and she attacks a Kalista Ward, it eats the powercord. The thing is, when attacking a traditional ward it does not eat the powercord, striking multiple times with powercord until the ward is dead.
When a buffed auto (Powerchord etc.) hits stuff like towers and wards, some of them often play the animation but don't use up the actual buff and just does a regular auto. Does the Kalista Sentry have a health pool or just bars which require you to auto attack a specific amount of times (like 3/5 for wards) to kill it? I don't recall because I haven't been playing much recently.
It has two bars, each having one life. Similar to a ward but requires just two hits. When attacking a ward with a buff auto such as PowerChord it does not use that buff. However, when attacking Kalista's ward, it does use the buff.
