Early game goal : behave like a normal soloq top player, join skirmishes (u're strong)
What to do after the 15 minute mark :
Don't be afraid to 1v1, take rift herald, generate sidelane pressure, never stop hitting towers until min. 2 people come to stop you, don't teleport when your team isn't fighting for objectives or ARAMing mid lane(since you are going to be the only person who's is active and they will 1v3, 1v4 you and teleport goes wasted),waste no time destroying towers as many as you can when your team fights for objectives and mid lane ARAMs, You are the Troll King They will ping because of not joining any teamfights and helping them take drakes, when you split push its 4v5 but when they see you destroying the inhi tower it will be 4v3 for sure cause no one can 1v1 Trundle(his R is designed for 1v1's), When you have to disengage and to escape 1v3's 1v2's hit enemy champions couple of times to get the movement speed from trinity force use ghost + w and get a burst of movement speed that is going to ensure your escape.

My Trundle OTP account (TR)

Do you think Karthus carried us and make them sit in the base at 20 minutes?
I started pushing with rift herald at 18:00 and enemy team ignored me thinking that I would back up after taking the 2nd outer turret and join the fight with tp. I finished the game by myself... destroying 4 turrets 1 inhi 1 nexus in 2 minutes. Your biggest advantage is that your enemies aren't used to playing against Trundle and the second being underestimating Trundle's tower taking power

I'll add the video of the last 2 minutes!!!!