Quilled Sliver

A 1/1 that turns a developed Sliver board into a battery of pinging archers, handing every Sliver tap-to-shoot firepower aimed at whatever steps into combat. Note the template: this uses the older symmetrical wording, so the grant covers all Slivers, including an opponent's, not just your own array. The output scales with the count, not the body: each additional Sliver is another shooter that can dome an attacker or blocker for a point, so a wide field becomes a crossfire that punishes anyone who commits creatures to it. The target restriction is what keeps the effect a combat-math tool rather than a reach engine: the damage can only hit a creature already attacking or blocking, never the player and never an untapped bystander. That gives a go-wide tribe a defensive gear it usually lacks, the Sliver that lets a wide board sit back and dare an attack. Two quirks run against intuition. The ability is a single tap, so each Sliver fires once per turn regardless of how many copies of this you control; a second Quilled Sliver adds a shooter, not a second shot from an existing one. And the grant is static, alive only while this is on the battlefield, so the entire array goes dark the instant the 1/1 leaves play. The whole defensive engine rides on a creature most removal can pick off, the cost of routing the tribe's firepower through one fragile node.