Top lane is mostly about winning trades. Riven is extremely strong at level 1. She likes to duel right in the beginning and is an early cheese champ. She will play aggressive against anyone who isn't Darius. She will shove the lane harder than he opponent in an attempt to outlevel the other player at every turn. If she is smart she will preemptively ward before making these trades.
Garen struggles against poke laners. Garen can outsustain the extremely passive laners and what Garen does best is counter attack. He will play passively and upon being engaged upon he will activate Q removing the slow and then run at his enemy, silence them and swing his sword at them as they run away. He then proceeds to zone them as his health regen is better than theirs. He could get kills but he also can outsustain people when they puss out and don't want to fight face to face. But the ones who Garen struggles against are the sissies who spam missiles at him and run away.
Shen is great. He's my favorite tank. Shen is pretty passive in lane. He will just farm under tower every chance he gets. His Q gives minimal poke but if you follow up on it he can des some decent damage through his passive and heal himself in the process. Shen also works great against poke style champions with his shield. Heck, he just ignores them completely through shield and Q and he taunts any silly poker who gets too close. He can tango against kill laners too and hold his own. The ones I find him struggling against are the passive sustain laners. Namely Nasus. Shen is best played passively and when he has to become the aggressor he doesn't have much to work with. He will need ganks to put down passive laners. The reason why Nasus gives Shen trouble I that Nasus can disengage Shen off him with his slow and heal away any of Shen's poke with his own Q. That and Nasus should never be alone in lane and Shen's ultimate takes him out of lane frequently. If against a Nasus ask for a lane swap at some point. Nasus needs constant attention and Shen is a bad step dad when it comes to giving puppies play time.
Early on Trundle counters aggressive laners. His Q steals some of their AD damage output so he wins trades against aggression. His W is good for maneuvering towards, around or away from his enemy. Its not flashy though. Pillar can be used to cut off escapes, screws up the enemy jungler's ganks (really pisses off Hecarim and Nocturne junglers early game), is his primary escape tool and can also interrupt channeled spells such as Shen, Vi, Sion and Galio. Trundles passive helps him stay in lane regardless of whether his minions or the enemy minions are pushing. This passive buffs Trundle up preparing him for what he does best: taking towers. W speeds up Trundle's attacks, Q can be used on towers as spammable auto attack reproc and if someone tanky comes to gank you you ult them and laugh while you take the tower anyway. Then pillar them and go about your business. Trundle is meant to destroy tanky champions through his ultimate. His ult allows him to build damage items and still be tanky, although that still is no excuse to go glass cannon Trundle. Build him bruiser items with 1 purely offensive item (I recommend blade of the ruined king) and late game strongly consider a tanky armor item like Frozen Heart or Thornmail so you can take out towers on your own. Just be sure to ward prior to doing this. Trundle can be semi-tanky but he still can't 1v5 an enemy team.
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