So, I just played my first normal game with a troll...
He locked Tahm ASAP, I took mid thinking he'd go support, he then decided to go jungle when we already had one, and once the game began the first thing he did was come up to mid to steal cs and spit me out as close as he could to the enemy. He then went for the mobility boots and began roaming the map, going to each lane and swallowing teammates to get them killed until we reached the 20 minute mark and were finally able to surrender.
The fact that the enemy team played along with his game was even more infuriating. I know that if a Tahm constantly came up to me to spit his teammates up as a trolling tactic I'd either focus him or just walk away, but I guess at my current rank people barely care about being good sports and will take any chances to get dem kills.