Hi I'm whybother34, a silver support main. This here is my Trundle guide. I think the troll is number 4 on my favorite supports list behind Leona Braum and Thresh (check out my Leo and Braum guide pls). I'll get right into the guide so theres no need to waste your time. Hey heres an update for a dead guide.

Pros
-Trundle provides a crazy amount of tank from his Kings Tribute passive Subjugate Ult and Frozen Domain W
-Restriction of enemy escape options with Pillar of Ice E and the ability to cancel channels with displacement
-Dueling potential while still being a tank support with Chomp Q and W
-Incredibly safe lanning phase with huge sustain from passive
-Can shred towers with W and Q
-Turning enemy tanks into squishies and you into a mega tank with your ult
Cons
-Melee support issues like getting poked
-No hard CC save the displacment from landing the E on someone
-The aftershock can be hard to get if you don't have practice with your E
-While sure W lets you chase, you dont really have a great engage
When to Pick Trundle
-When the enemy team has 1 tank
-when the enemy team has a Malphite,Rammus,Sejuani
-When the enemy team has a Sion

Early game you have a very safe laning phase due to your healing from your passive and increased healing from your w and more healing from your relic shield. Your E makes it very hard for people to escape if you land a good one, unless they have a Tahm Kench or its a Rakan or Ezreal. I really enjoy playing trundle into sivir since she can't spell shield a pillar.
Mid game you can make good roams when your adc is backed if you have a mid laner with some cc. don't w too early or they will see the ice before you show yourself and you blew the gank. At this point you also have some points into your W and with demolish you can be a split push threat (also with iceborn).
Late game when teamfights start you pick out their tank and go "hey you let me take your stats" and ult him. Thats the go sign for you team to dive the tank since they lost most of their tank stats. You engage with the w, pillar off the squishies and chase them down. You also now have a maxed W and can really put the hurt in on towers. If you're not doing anything always try and split push since most supports don't have that capability. You're Trundle you're not like other supports.

More to come later