Here is a character I played, in a one fight game here on enworld.
[sblock=Basics]
Name: Morgrim
Class: Fighter/Avalanche hurler
Alignment: Good
Race: Dwarf
Deity: Moradin
Size: Medium
Age: 42
Gender: Male
Height: 4' 6"
Weight: 190 lbs
Eyes: Green
Hair: black
Abilities
Str: 21 [+5], Dex: 15 [+2], Wis: 18 [+4]
Con: 20 [+5], Int: 11 [+0], Cha: 9 [-1]
Hit Points: 139 Bloodied: 69
Healing Surges: 16/day Healing Surge hp gained:39 HP
Action Points: 1
Speed: 5 squares
Armor Class: 34(36 until hit)
Fortitude Defence: 33
Reflex Defence: 31(33 until hit)
Will Defence: 30
Initiative: +12
Skills:
Athletics +20
Endurance +22
Heal +19
Perception +19
Languages: Common, Dwarven
[/sblock]
[sblock=Feats]
1 Two Weapon Fighting (+1 damage w/main hand when using two weapons)
1 Two weapon defense (+1 shield bonus to AC and Reflex when using 2 weapons, bonus)
2 Two-bladed warrior (skill training w/ ranger skill, can use 1 handed weapon in off-hand, multi-class ranger feat)
4 Dwarven weapon training(prof and +2 dam w/ axe and hammers)
6 Dwarven durability (+2 healing surge, +5 to surge value, retrained)
8 Adept power(Ranger)
10 Grit (When spending a healing surge gain 5 temp hp)
11 Enduring Wallop (Ongoing 5 damage with fighter daily attack)
12 Lightning reflexes(+2 to ref def)
14 Hammer Rhythm(con damage on a miss)
16 Armor Spec(chainmail, +1 AC and ACP with chainmail)
18 Agile Tempest(+1 damage with tempest damage bonus)
20 Marked Scourge (+4 damage vs marked enemies)[/sblock]
[sblock=Race Traits]
Vision: Low-light
Skill Bonuses: +2 Endurance(included), +2 Dungeoneering
Cast iron stomach: +5 on saves vs poison
Dwarven resilience: Second wind as minor action
Encumbered speed: speed not reduced by heavy armor
Stand your ground: Forced movement moves 1 less square. Make saving throw to avoid going prone from attack[/sblock]
[sblock=Fighter Abilities]
Combat Challenge: On an attack can mark foe. When marked foe that is adjacient shifts or makes an attack that doesn't include me, I can take a melee basic attack as an immediate interrupt.
Combat Superiority: +4 bonus on opportunity attacks, an enemy struck by my opp attack stops moving.
Tempest Technique: Two weapon def as bonus feat. +1 to attack with weapons that have off-hand quality. +2 to damage while wielding two weapons and wearing chainmail or lighter armor. +3 to damage if using weapons with the off-hand quality.
Throwing Action: When spend an AP to take an extra action, I can make a ranged basic attack as a free action, not provoking OA.
Throwing Master: Increase the size by one die of a thrown weapon.
Uncanny Thrower: Take no penalty for throwing a weapon at long range.
[/sblock]
[sblock=Opportunity attacks]
Opportunity Attack: +27 vs AC 1d10+17
Ranged Opportunity Attack(spitting cobra stance): +25 vs AC 1d8+14
[/sblock]
[sblock=At-Wills]
Dual Strike, +22/21 vs AC(two attack, main off), 1d10+12/1d10+10.
Crushing Surge, +22 vs AC, 1d10+17 and gain 5 temp hp.
Basic Attack: +22 vs AC, 1d10+17 or +21 vs AC 1d10+15
Ranged Basic Attack: +21 vs AC, 1d8+14
Quick Draw Trick: Free action, I can draw or stow one or two weapons
Pass Forward: Move action, Pick an adjacient enemy and move up to your speed. As long as I stay adjacient, I don't provoke OA from that opponent.
[/sblock]
[sblock=Encounter Powers]
Two-fold Torment, +22 vs AC(two attacks), 1d10+17/1d10+15, push 3 squares and if have CA do 2 extra damage on each hit.
Appalling Crunch, +22 vs AC, 3d10+17, enemies within 2 squares of the target are marked. gain 5 temp hp
Landslide Strike, Can shift two squares before the attacks +22/21 vs AC(two attacks), 2d10+19/2d10+17(melee, main/off), or +21 vs AC(two ranged attacks, different targets), 2d8+16.
Boggling Smash, +22 vs AC, 3d10+22, the target is dazed and takes a -2 to attacks until end of my next turn.
Unbreakable, Immed Reaction, when hit by an attack, reduce the damage by 10
Bolstering Stride, Move action, Move 5 squares, ending adjacient to an ally and gain 2d8+5 temp hp.
Strikebacks(Immed React): Make a melee basic att against an adjacient foe that hits me.[/sblock]
[sblock=Daily attacks]
Defensive Resurgance: Minor Action. I can spend a healing surge and gain a +2 to AC until the start of my next turn.
Spitting Cobra Stance: Minor Action, As an opportunity action you can make a ranged basic attack against any enemy within 5 squares that moves closer to you.
Quicksilver Stance: Minor Action, I can shift one square as a move action and make a basic attack, if I have combat advantage the attack does an extra 4 damage
Smash and Grab: Must have a hand free, +22 vs AC, 3d10+22 and I grab the target, each time I sustain the grab I do 1d10+17 damage.
Eruption of Steel: (Melee. Two attacks, main/off)+22/21 vs AC. 2d10+19/2d10+18(miss half damage). Make a secondary attack against a different creature +22/21 vs AC. 1d10+19/1d10+18(miss half damage)
If ranged: Primary attacks: +21/+21 vs AC. 2d8+16/2d8+16(miss for half): Secondary attacks, must be against two different targets: +21/+21 vs AC. 1d8+16/1d8+16(miss for half)[/sblock]
[sblock=Magic Item Daily Powers 2/day +1 per milestone]
Voidcrystal Armor: Immed Reaction, use when att misses my AC. Weapon used to attack does half dam(save ends), if attacker was unarmed, instead they take ongoing 10 dam(save ends)
Battering Craghammer: Make a melee basic attack vs all enemies in a blast 3.
Dwarven Boots(Immed Inter): Use when power would push, pull, slide, or knock prone. Attacker rerolls and used second attack even if lower.
Cloak of displacement: II: Use when hit by melee or ranged att, Attacker must reroll and use second result even if lower, if attacker misses I can teleport one square.[/sblock]
[sblock=Gear]
Money: 200gp
Battering Craghammer+5(21)
Crysteel Voidcrystal Armor +4(19)
Cloak of Displacement +4(20)(each encounter gain a +2 bonus to AC and Ref until an attack hits)
Bloodclaw Craghammer +4(take up to 4 damage and deal double that amount to target of attack, +4d6 on crit)(65000gp)
Throwing hammer +3(9000gp)
Iron armbands of power(+2 damage to melee attacks)(1800gp)
Strikebacks(5000gp)(+1 to hit on opp att)
Dwarven Boots
Backbone Belt(after second wind gain +4 to defenses)
2 potions of vitality(minor, spend surge, but regain 25hp and make a save)
[/sblock]
I was never really able to play him to full effect(like I said, 1 encounter). I didn't max Wis, because I wanted hammer rhythym and good damage on a miss.
Overall, I don't think marked scourge is bad. It is a paragon feat, which we are liable not to see for a long time here. You really have to focus on it to get good damage out of it. On fighter being a striker, than can sort of be their secondary role, just like other classes have secondary roles. The above combo is limited, because it does use dailes and AP, so it can't be done all the time as well.
If it had to be limited, I would say: once per opponent per standard action.