Assuming no LOS at this point:

Stewie, Round 2:

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Swift: Activate midnight metamagic, allocating 2 essentia. Name Magic Missile and Fell Drain. Next magic missile will be automatically affected by Fell Drain.
Move: Move to J16
Standard: Ready Action: Cast Magic Missile if LOS and LOE is established between myself and my opponent. Target will be my opponent.


If LOS has been established, use this instead:
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Swift: Activate midnight metamagic, allocating 2 essentia. Name Magic Missile and Fell Drain. Next magic missile will be automatically affected by Fell Drain.
Standard: Cast magic missile, targeting Opponent. Damage: (1d4+1)[3]
... and a negative level.


Done.

Stats:
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Location: J16 or F15
HP: 9/9
AC: 13 / 10 FF
Essentia: 2/2, Invested-Midnight Metamagic
Spells: 5 / 4 (or 5/3)
Effects: Travel Devotion 2/10