A question on this, and I am not being snarky - what 4e Swordmage ability allows you to do this? I did not play 4E a lot and never played a Swordmage, but I see a lot of people talk about this thing, but don't see it on any of the Swordmage class abilities.
Flipping through the FR Player's Guide I found:
Hell’s Own Blade Swordmage Attack 19
You hurl your sword, and it buries itself into the chest of a distant foe. Your sword explodes, sending waves of roiling flame out in all directions, before reforming in your hand.
Daily ✦ Arcane, Fire, Weapon
Standard Action Ranged 10
Primary Target: One creature
Attack: Intelligence vs. AC
Hit: 1[W] + Intelligence modifier fire damage.
Effect: Make a secondary attack.
Secondary Targets: The primary target and each enemy within 2 squares of it
Secondary Attack: Intelligence vs. Reflex
Hit: 3d8 + Intelligence modifier fire damage.
Miss: Half damage.
It seems familiar, I think I had it when I was playing epic.