Currently on the pbe, thornmail is a component that builds into randuin's omen. Personally I really love the idea, since it makes both items more useful or impactful.
Which leaves me to wonder if there are more items that can use said treatment. Ohmn and banner are intended to be siege items, but not only are they rarely built, they seem to pale in comparison to the portal.
Warlord Scrap1 votesBut ohmwrecker and boc both have actives. 2 actives with 2 cooldowns would be difficult to implent unless the changed the boc back to its passive aura form
Mysticman891 votesPerhaps make it a single context sensitive active then? Use the active on a minion and it promotes, use it on a tower and it disables. Probably a shared cooldown, but you probably don't need both very often.
Chromatic Eagle1 votesThey could make a super duper minion that takes reduced tower damage or immunity. Banner could also maybe empower the team against towers.