Shadow Darts, Cloaking Mist, and Targeted For Death, are all non-teleport powers. Two of them ranged, and one is a close blast.
I can use the Garrote as an implement (Ki focus), and still get combat advantage from my grabbed target. Two of the powers above would provoke, one wouldn't.
As for the At-will powers, as a human I got three, so I picked powers that made the best use of the Garrote.
The only teleporting he does is with Shadow Step, and I get control over that.
[sblock=CB summary]
====== Created Using Wizards of the Coast D&D Character Builder ======
LEB assassin concept, level 4
Human, Assassin
Guild Training: Bleak Disciple
Blood Drain: Blood Drain Dexterity
Background: Liondrake's Roar Mercenary (+2 to Dungeoneering)
FINAL ABILITY SCORES
Str 14, Con 16, Dex 18, Int 10, Wis 8, Cha 13.
STARTING ABILITY SCORES
Str 14, Con 15, Dex 15, Int 10, Wis 8, Cha 13.
AC: 19 Fort: 18 Reflex: 18 Will: 16
HP: 38 Surges: 9 Surge Value: 9
TRAINED SKILLS
Arcana +7, Stealth +11, Perception +6, Endurance +10, Athletics +9, Acrobatics +11, Thievery +11
UNTRAINED SKILLS
Bluff +3, Diplomacy +3, Dungeoneering +3, Heal +1, History +2, Insight +1, Intimidate +3, Nature +1, Religion +2, Streetwise +3
FEATS
Human: Vampiric Heritage
Level 1: Garrote Training
Level 2: Improved Grab
Level 4: Sneak of Shadows
POWERS
Assassin at-will 1: Leaping Shade
Assassin at-will 1: Shadow Storm
Bonus At-Will Power: Executioner's Noose
Assassin encounter 1: Shadow Darts
Assassin daily 1: Targeted for Death
Assassin utility 2: Cat's Trickery
Assassin encounter 3: Cloaking Mist
ITEMS
Bloodclaw Garrote +2, Deathcut Leather Armor +1, Brooch of Shielding +1, Belt of Resilience (heroic tier), Fine Clothing, Backpack (empty), Camouflaged Clothing, Disguise Kit, Climber's Kit, Footpads, Glass Cutter, Hunter's Kit, Identification Papers, with Portrait, Inquisitive's Kit, Rope, hempen (50 ft.) (2), Rope, Silk (50 ft.), Thieves' Tools
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