I don't think you applied the life gain. Which really puts a damper on my chances here.
Untap, Upkeep, Draw
Cast Soltari Trooper, give Avenger shadow and vigilance, attack with Avenger, done
Melkor: 1
Hand: 1
Library: 25
Battlefield:
(U) (U) (T) Island x3
(U) (U) (T) (U) Plains x4
Gaseous Form (Enchanted creature neither deals nor receives combat damage)
(U) Shinewend (1/1, Flying, W1, Remove a +1/+1 counter from ~: Destroy target enchantment, ~ comes into play with a +1/+1 counter on it)
(U) Jodah's Avenger (4/4, 0: Until end of turn, Jodah's Avenger gets -1/-1 and gains your choice of double strike, protection from red, vigilance, or shadow.
(U) Minister of Impediments (1/1, T: Tap target creature)
(S) Soltari Trooper (1/1, Shadow, ~ gains +1/+1 whenever it attacks)
Graveyard: Time Ebb, Fencer Clique
Exile:
----------------------------------------------------------------------------------------
Mooseman: 13 11? 24?
Hand: 0
Library:25
Battlefield:
(UTT) Plains x3
(UUUTT) Forest x5
(T) Borderland Ranger (2/2, ETB: you may search your library for a basic land card, reveal it, and put it into your hand. )
(T) Gravel Slinger (1/3, Tap: Gravel Slinger deals 1 damage to target attacking or blocking creature. Morph 1W)
(U) Kithkin Spellduster (2/3, Flying 1W, Sacrifice Kithkin Spellduster: Destroy target enchantment. Persist ) -Gaseous-
(T) Freewind Falcon (1/1, Flying, protection from red)
Graveyard: Taunting Elf
Exile: