Sylvan Basilisk

Whenever Sylvan Basilisk becomes blocked by a creature, destroy that creature.

Laccolith Whelp

Whenever Laccolith Whelp becomes blocked, you may have it deal damage equal to its power to target creature. If you do, Laccolith Whelp assigns no combat damage this turn.

Neyith of the Dire Hunt

Whenever one or more creatures you control fight or become blocked, draw a card.
At the beginning of combat on your turn, you may pay {2}{R/G}. If you do, double target creature's power until end of turn. That creature must be blocked this combat if able. ({R/G} can be paid with either {R} or {G}.)

Deepwood Wolverine

Whenever Deepwood Wolverine becomes blocked, it gets +2/+0 until end of turn.

Dwarven Berserker

Whenever Dwarven Berserker becomes blocked, it gets +3/+0 and gains trample until end of turn.

Karplusan Wolverine

Whenever Karplusan Wolverine becomes blocked, you may have it deal 1 damage to any target.

Viashino Weaponsmith

Whenever Viashino Weaponsmith becomes blocked by a creature, Viashino Weaponsmith gets +2/+2 until end of turn.

Elven Warhounds

Whenever Elven Warhounds becomes blocked by a creature, put that creature on top of its owner's library.

Ichorclaw Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever Ichorclaw Myr becomes blocked, it gets +2/+2 until end of turn.

Rust Scarab

Whenever Rust Scarab becomes blocked, you may destroy target artifact or enchantment defending player controls.

Thresher Beast

Whenever Thresher Beast becomes blocked, defending player sacrifices a land of their choice.

Somberwald Vigilante

Whenever Somberwald Vigilante becomes blocked by a creature, Somberwald Vigilante deals 1 damage to that creature.

Likeness of the Seeker

Whenever Likeness of the Seeker becomes blocked, untap up to three lands you control.

Azusa's Many Journeys

(As this Saga enters and after your draw step, add a lore counter.)
I — You may play an additional land this turn.
II — You gain 3 life.
III — Exile this Saga, then return it to the battlefield transformed under your control.