Teysa Karlov
Teysa Karlov
If a creature dying causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Creature tokens you control have vigilance and lifelink.
While Kaya is guildmaster, Teysa waits patiently at the center of the Orzhov web of power.
illus. Magali Velleneuve # 212/259

Oracle Text
If a creature dying causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Creature tokens you control have vigilance and lifelink.
Off the top of my head, Doomed Dissenter, Deathbloom Thallid, Martyr of Dusk and the newly spoiled Seraph of the Scales all look really good with Teysa. Good stuff.
And don't forget, it also applies to other things, as long as the permanent going to the graveyard is in fact a creature. So if you have a Femeref Enchantress and someone kills your, I don't know, Archetype of Finality, you get a Divination. If you have a Disciple of the Vault and your Wurmcoil Engine dies, Disciple triggers twice and (per Wurmcoil) you get two of each token. If you have something like Dryad Arbor and Titania, Protector of Argoth and the former dies, you get two 5/3s.
Just remember, one of the persist/undying triggers fizzles.