Clamavus

Most anthem effects hand the team a flat bonus; this one scales with a resource the deck is already grinding toward. The Proclamator Hailer clause doubles the effective size of every +1/+1 counter you have placed, so a creature carrying three counters is not gaining +1/+1 from an anthem, it is gaining +3/+3. That inverts the usual counters math. In a typical counters deck the counters are the payoff and any anthem is incidental; here the anthem is the multiplier and the counters are the fuel, so the value of every proliferate trigger, every graft, every adapt or reinforce climbs the moment this hits the battlefield. Think of it as a green-native cousin of the doubling family: instead of copying tokens or damage, it converts stored counters into an ongoing static boost that reads across every creature you control at once. That static nature is also the real constraint. A 3/3 body sitting behind a board of counter-laden threats is exactly the target removal is happy to trade with, and when it dies the boost evaporates: your creatures keep the +1/+1 counters they earned, but they snap back to that counter-only size, no longer paying double. It rewards a board built wide on counters rather than tall on a single stacked creature, since a swarm of modestly enhanced bodies all double their counters simultaneously into a lethal alpha strike.