Glint-Horn Buccaneer

Haste
Whenever you discard a card, this creature deals 1 damage to each opponent.
{1}{R}, Discard a card: Draw a card. Activate only if this creature is attacking.

Jumpstart 2022

Haste
Whenever you discard a card, Glint-Horn Buccaneer deals 1 damage to each opponent.
{1}{R}, Discard a card: Draw a card. Activate only if Glint-Horn Buccaneer is attacking.

Core Set 2020

Haste
Whenever you discard a card, Glint-Horn Buccaneer deals 1 damage to each opponent.
{1}{R}, Discard a card: Draw a card. Activate this ability only if Glint-Horn Buccaneer is attacking.

Core Set 2020 Promos

In a Two-Headed Giant game, Glint-Horn Buccaneer’s triggered ability causes the opposing team to be dealt 1 damage twice.

The middle ability of Glint-Horn Buccaneer is a triggered ability, not an activated ability. It doesn’t allow you to discard a card whenever you want; rather, you need some other way of discarding a card, such as by activating its last ability.