An Unearthly Child

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II, III — Reveal cards from the top of your library until you reveal a Doctor card, a card with doctor's companion, or a Vehicle card. Put that card into your hand and the rest on the bottom of your library in a random order.

Tom Bombadil

As long as there are four or more lore counters among Sagas you control, Tom Bombadil has hexproof and indestructible.
Whenever the final chapter ability of a Saga you control resolves, reveal cards from the top of your library until you reveal a Saga card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. This ability triggers only once each turn.

Ajani Fells the Godsire

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Exile target creature an opponent controls with power 3 or greater.
II — Create a 2/1 white Cat Warrior creature token, then put a vigilance counter on a creature you control.
III — Target creature you control gains double strike until end of turn.

Arni Slays the Troll

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Target creature you control fights up to one target creature you don't control.
II — Add {R}. Put two +1/+1 counters on up to one target creature you control.
III — You gain life equal to the greatest power among creatures you control.