While the term often refers to creatures with activated abilities that tap creatures, like Benalish Trapper and Gideon's Lawmaker, it encompasses ETB triggers, instants, sorceries, and planeswalkers that tap opposing permanents
In some ways, its like a Cultivate, but instead of a land in your hand, you effectively get a six-mana draw-two
For instance Download card art for the alts you want to display: Update: A helpful person has collated all of the current alternate arts
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.) Balamb T-Rexaur Rarity: Common TYPE: Creature SUBTYPE: Dinosaur CMC: 6 Mana cost: USD: $0.15 EUR: 0.07 TIX: 0.03 EDHREC RANK: 11440 (6/6) Trample When this creature enters, you gain 3 life
If the baseline for that is one card, what would I have to add to convince you this was a very good card