Martyr's Bond is a rare Enchantment card from Signature Spellbook: Gideon (SS2), collector number 2. Current market price: $0.46 (foil $1.36), TCGplayer market prices via Scryfall.
Whenever this enchantment or another nonland permanent you control is put into a graveyard from the battlefield, each opponent sacrifices a permanent of their choice that shares a card type with it.