Supportive Parents

Tap two untapped creatures you control: Add one mana of any color.

Spider-Man India

Web-slinging {1}{G}{W} (You may cast this spell for {1}{G}{W} if you also return a tapped creature you control to its owner's hand.)
Pavitr's Sevā — Whenever you cast a creature spell, put a +1/+1 counter on target creature you control. It gains flying until end of turn.

Spider Manifestation

Reach
{T}: Add {R} or {G}.
Whenever you cast a spell with mana value 4 or greater, untap this creature.

Spiders-Man, Heroic Horde

Web-slinging {4}{G}{G} (You may cast this spell for {4}{G}{G} if you also return a tapped creature you control to its owner's hand.)
When Spiders-Man enters, if they were cast using web-slinging, you gain 3 life and create two 2/1 green Spider creature tokens with reach.

Waterbending Lesson

Draw three cards. Then discard a card unless you waterbend {2}. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Stubborn Burrowfiend

Whenever this creature becomes saddled for the first time each turn, mill two cards, then this creature gets +X/+X until end of turn, where X is the number of creature cards in your graveyard.
Saddle 2 (Tap any number of other creatures you control with total power 2 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Gloryheath Lynx

Lifelink
Whenever this creature attacks while saddled, search your library for a basic Plains card, reveal it, put it into your hand, then shuffle.
Saddle 2 (Tap any number of other creatures you control with total power 2 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Heirloom Epic

{4}, {T}: Draw a card. For each mana in this ability's activation cost, you may tap an untapped creature you control rather than pay that mana. Activate only as a sorcery.

Hemosymbic Mite

Whenever this creature becomes tapped, another target creature you control gets +X/+X until end of turn, where X is this creature's power.

Cynical Loner

This creature can't be blocked by Glimmers.
Survival — At the beginning of your second main phase, if this creature is tapped, you may search your library for a card, put it into your graveyard, then shuffle.

Flash Thompson, Spider-Fan

Flash
When Flash Thompson enters, choose one or both —
• Heckle — Tap target creature.
• Hero Worship — Untap target creature.

Veteran Beastrider

At the beginning of your end step, untap each creature you control.
{2}{G}{W}: Creatures you control get +1/+1 until end of turn.

Fire Navy Trebuchet

Defender, reach
Whenever you attack, create a 2/1 colorless Construct artifact creature token with flying named Ballistic Boulder that's tapped and attacking. Sacrifice that token at the beginning of the next end step.

Spider-UK

Web-slinging {2}{W} (You may cast this spell for {2}{W} if you also return a tapped creature you control to its owner's hand.)
At the beginning of your end step, if two or more creatures entered the battlefield under your control this turn, you draw a card and gain 2 life.

Rover Blades

Double strike
Equipped creature has double strike.
Equip {4}
Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn. Creatures can't be attached to other permanents.)

Wild Ride

Target creature gets +3/+0 and gains haste until end of turn.
Harmonize {4}{R} (You may cast this card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by {X}, where X is its power. Then exile this spell.)

Dragonbroods' Relic

{T}, Tap an untapped creature you control: Add one mana of any color.
{3}{W}{U}{B}{R}{G}, Sacrifice this artifact: Create a 4/4 Dragon creature token named Reliquary Dragon that's all colors. It has flying, lifelink, and "When this token enters, it deals 3 damage to any target." Activate only as a sorcery.