Riven

Riven is a 4-cost Timebreaker and Rogue champion that usually plays as a frontline sustain unit. Its sustain or shielding makes it valuable when it survives long enough to buy time for the rest of the board. Riven appears in Cards & Cartridges and Stay Groovy lines, so keep copies when those boards are open.

Consider playing around Riven when you can level cleanly and find key copies on the rolldown. For items, Bloodthirster and Sterak's Gage are strong signals that Riven can stay on the board. For team direction, it fits naturally when you are already moving toward Cards & Cartridges and Stay Groovy. If it stays one-star, the traits do not activate, or the items point elsewhere, treat it as a transition unit instead of forcing the line.

Bloodthirster, Sterak's Gage and Titan's Resolve are recommended. Bloodthirster adds sustain and a low-health shield for extended melee fights, Sterak's Gage gives a health spike so the unit survives the first focus window and Titan's Resolve rewards long fights with stacking damage and durability. The point of the setup is to keep it alive long enough to cast and hold the frontline.

When the perfect setup is not available, use Hand Of Justice, Edge of Night, Warmog's Armor and Steadfast Heart as substitutes. For frontline substitutes, prioritize durability, sustain, and opening damage reduction without stealing every carry item. If Riven is only a trait slot, one useful item is enough and the premium items should go to your real carry or main tank.

Early: play strongest board while keeping components that fit Riven. Mid game: level toward the rolldown that can find a two-star copy. Late game: build around Timebreaker and Rogue and add either frontline, control, or secondary damage so the board is not one-dimensional.

Place Riven in the first row on a side, or in the second row when it needs protection. It should enter combat quickly without eating every enemy attack at once. Its mana bar is short, so surviving lets it cast repeatedly.