Is it possible to change Kalista's bound ally?
No this is not possible.
You can only rebind within 3minutes into the game
http://na.leagueoflegends.com/en/news/game-updates/patch/patch-421-notes#patch-kalista
No this is not possible.
You can only rebind within 3minutes into the game
http://na.leagueoflegends.com/en/news/game-updates/patch/patch-421-notes#patch-kalista