They key to renek is fury management, his damage goes WAY up if you can use it right.
AD quints AD or armor pen marks Armor seals MR per level glyphs
9-21-0 take the reduced champion damage, helps top lane)
Flash ignite or exhaust Open boots + 3 pots Start Q, e at level 2, and w at 3...you want your full combo quickly R Q E W max order
Only bother going for your combo with 50 fury. In general you will E in, use either a fury boosted Q or W, use the ability that was not boosted, and E back out. The decision on what to use fury on depends on how well you doing...not taking much damage? Hit then with enhanced stun. Want to abuse your sustain, enhanced Q
For using your ult, in lane phase wait till someone commits on you before using it, it's an amazing bait tool. Mean trick if you are ready to kill is to ult while hidden in bush, wait till max fury...then dive for enhanced QW and ignite. Teamfights just ult ASAP to abuse your damage aura and get more fury enhanced abilities off
First back should either be dorans, brutalizer, or phage. Don't bother with Ionian boots unless your stomping hard, the defenses from mercs/tabi is a lifesaver
My general final build is: Tabi/mercs (sometimes Ionian) Black cleaver Frozen mallet Maw Randuins Last whisper (bloodthirster if not a lot of armor on other team
Also, wards are EXTREMELY important on him since his harass pushes the lane hard
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