Panharmonicon Doesn't Double Counters
Judge Level 2The trigger fires twice — but "enters with X counters" isn't a trigger at all.
Cards involved
The double trigger
You control Panharmonicon ("If an artifact or creature entering the battlefield causes a triggered ability of a permanent you control to trigger, it triggers an additional time"). You cast Wall of Omens ("When this creature enters, draw a card").
The Wall lands
Its ETB trigger fires TWICE — both triggers go on the stack individually, each can be responded to individually. You draw two cards.
What happens?
Now the trick question.
You cast Walking Ballista with X=2. Does Panharmonicon make it enter with 4 counters?
Pick an answer to continue.
"Enters with …" modifies the entering event itself and is a replacement (614.1c) — it never uses the stack. Panharmonicon, however, only reads triggered abilities ("when/whenever …"). The Ballista enters with exactly 2 counters.
614.1cEffects that read “[This permanent] enters with . . . ,” “As [this permanent] enters . . . ,” or “[This permanent] enters as . . . “ are replacement effects.
The rule of thumb
"WHEN it enters, DO …" = trigger (stack, respondable, Panharmonicon applies). "Enters WITH …" = replacement (no stack, no response window, Panharmonicon useless — but counter doublers like Corpsejack Menace do apply).
614.1cEffects that read “[This permanent] enters with . . . ,” “As [this permanent] enters . . . ,” or “[This permanent] enters as . . . “ are replacement effects.
603.6dSome permanents have text that reads “[This permanent] enters with . . . ,” “As [this permanent] enters . . . ,” “[This permanent] enters as . . . ,” or “[This permanent] enters tapped.” Such text is a static ability—not a triggered ability—whose effect occurs as part of the event that puts the permanent onto the battlefield.
Stack
Panharmonicon
ETB triggers of artifacts/creatures trigger an additional time
Wall of Omens
When it enters: draw a card
Walking Ballista
Enters with X +1/+1 counters — X=2
The stack is empty.
Battlefield
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