Trundle is a very tanky DPS who also has 2 utility abilities. Trundle does really well in the jungle because of his awesome ganks and can clear the jungle quick. Trundle also is a great solo top since his passive gives him good sustain.

I took these runes to be tanky but able to still do decent damage. I Take the MS Quins because I like to take a Heart of Gold before completing my Boots of Swiftness. It allows me to still be able to move around the jungle while still having the 5GPS.

I use Phreak's Build from the Champion Spotlight just because it gives me some damage and attack speed from the Madred's Bloodrazor, but I'm still very tanky. I take Boots of Swiftness because I like to chase as Trundle. Other good boots would be Mercury's Treads or Ninja Tabi. Once you get your Frozen Mallet and Madred's Bloodrazor You're most likely going to be successful with your ganks if you place your Pillar of Filth in the right spot. Banshee's Veil is taken for the passive and the MR, another good choice would be a Force of Nature. VERY IMPORTANT - Don't forget to use your Randuin's Omen if the game is still going on for you to even get that.

Very self explanatory Skill Build. Rabid Bite is always first no matter if your lanning or jungling Since Pillar of Filth doesn't get bigger each rank it's best to take that last and stick with Contaminate. As always put a point into your ult Agony whenever you can.

Recommended

Smite - Take this as a Jungler most of the time
Ghost - I like taking this because I like to chase as I said before but there are still other spells that are good choices.
Flash - Good choice for juking and flashing over walls. Also goes well with Pillar of Filth
Exhaust - Not the Best since you will have a Frozen Mallet but i guess the Armor and MR reduction is good
Ignite - You have better choices but this is good for those Healers or People that get away with 1 bar of health

DO NOT TAKE

Revive - Even with the Buff it still isn't worth it
Clarity - Mana isn't a problem mid and late game and early game you will usually have Blue Buff
Surge - I don't want to sound ignorant but this spell is just stupid
Promote - You Don't Need this if your jungling