Capitano dei Sigilli {1}{G}{W}{W}

Creatura — Soldato Rinoceronte

Ogniqualvolta una creatura entra nel campo di battaglia sotto il tuo controllo, se quella creatura è 1/1, metti due segnalini +1/+1 su di essa.

“Un sigillo riconosciuto per il valore, l'altro per essere sopravvissuto al Passo dei Nibbi Infernali.”

3/3

Illustrated by Howard Lyon

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Only the English version of a Magic card receives Oracle updates and errata. View this card in English. (Scryfall note)
Sigil Captain's ability has an "intervening 'if' clause." That means (1) the ability won't trigger at all unless the creature that enters under your control is 1/1, and (2) the ability will do nothing unless that creature is still 1/1 at the time the ability resolves. (2009-05-01)
For that reason, two Sigil Captains don't work well together. When a 1/1 creature enters under your control, the abilities of both Sigil Captains will trigger. When the first resolves, two +1/+1 counters are put on the 1/1 creature. When the second resolves, it will do nothing because the creature that entered is now 3/3. (2009-05-01)

Sigil Captain's ability checks a creature's initial power and toughness upon being put on the battlefield, so it will take into account counters that it enters with and static abilities that may give it a continuous power boost once it's on the battlefield (such as the one on Glorious Anthem). After the creature is already on the battlefield, changing its power and toughness to 1/1 with a spell, activated ability, or triggered ability won't allow this ability to trigger; it's too late by then. (2009-05-01)
If, for some reason, Sigil Captain enters as a 1/1 creature (due to a pair of Engineered Plagues, for example), it will cause its own ability to trigger. (2009-05-01)