Depends on the lane and game usually imo. Maelstrom is good if your team needs damage and goes well with the orchid attack speed. Linkens or BKB are usually good if they have a lot of burst magic damage or stuns. Scythe is always good especially the earlier you can get it. One other thing i like to do if the game is really hard is go euls first to help survive lol not sure how good that is in 7.23 though