Renegade Wheelsmith

Whenever Renegade Wheelsmith becomes tapped, target creature can't block this turn.

Scaretiller

Whenever Scaretiller becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

Wildfire Awakener

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
When Wildfire Awakener enters, create X 1/1 red Elemental creature tokens with "Whenever this creature becomes tapped, it deals 1 damage to target player."

Emmara, Soul of the Accord

Whenever Emmara, Soul of the Accord becomes tapped, create a 1/1 white Soldier creature token with lifelink.

Annie Flash, the Veteran

Flash
When Annie Flash, the Veteran enters, if you cast it, return target permanent card with mana value 3 or less from your graveyard to the battlefield tapped.
Whenever Annie Flash becomes tapped, exile the top two cards of your library. You may play those cards this turn.

Radha, Coalition Warlord

Domain — Whenever Radha, Coalition Warlord becomes tapped, another target creature you control gets +X/+X until end of turn, where X is the number of basic land types among lands you control.

Quest for Renewal

Whenever a creature you control becomes tapped, you may put a quest counter on Quest for Renewal.
As long as there are four or more quest counters on Quest for Renewal, untap all creatures you control during each other player's untap step.

Depala, Pilot Exemplar

Other Dwarves you control get +1/+1.
Each Vehicle you control gets +1/+1 as long as it's a creature.
Whenever Depala, Pilot Exemplar becomes tapped, you may pay {X}. If you do, reveal the top X cards of your library, put all Dwarf and Vehicle cards from among them into your hand, then put the rest on the bottom of your library in a random order.

Wylie Duke, Atiin Hero

Vigilance
Whenever Wylie Duke, Atiin Hero becomes tapped, you gain 1 life and draw a card.