Cheapest priced copy (Aetherdrift): $1.29 at Card Kingdom, near mint, their price list as of .
Mendicant Core, Guidelight 
Legendary Artifact Creature — Robot · */3 · Rare · Aetherdrift Promos · #213p
Mendicant Core's power is equal to the number of artifacts you control.
Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.)
Max speed — Whenever you cast an artifact spell, you may pay {1}. If you do, copy it. (The copy becomes a token.)
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
5 printings · $1.29 to $9.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Aetherdrift | 213 | Rare | $1.29 | $1.49 |
| Aetherdrift | 365 | Rare | $2.49 | $4.99 |
| Aetherdrift | 485 | Rare | — | $9.99 |
| Aetherdrift Promos | 213p | Rare | $1.29 | $1.49 |
| Aetherdrift Promos | 213s | Rare | — | $2.99 |
8 rulings from Wizards of the Coast
- 7 February 2025“Max speed — [ability]” means “As long as you have max speed, this object has [ability].” If the granted ability functions in a zone other than the battlefield, the max speed ability does too.
- 7 February 2025If an effect needs to know what a player’s speed is and that player doesn’t have a speed, their speed is considered 0.
- 7 February 2025The copy remembers any decisions that were made for the original spell as it was cast, including values chosen for X in its mana cost and whether any alternative or additional costs were chosen. For example, if the original artifact spell had kicker and its kicker cost was paid, the copy will also be kicked.
- 7 February 2025A resolving copy of a permanent spell becomes a token, so the token isn’t “created.” Effects that care about a token being created won’t interact with a token that enters the battlefield from Mendicant Core’s last ability.
- 7 February 2025A player “has max speed” if their speed is 4.
- 7 February 2025Start your engines! isn’t a triggered ability. Increasing your speed to 1 is something that happens as a state-based action as soon as you control a permanent with the ability. Notably, this includes gaining control of a permanent with the ability that another player controls.
- 7 February 2025Your speed doesn’t change until a spell or ability says so, such as the inherent triggered ability that cares about opponents losing life during your turn. Notably, losing control of permanents with start your engines! doesn’t affect your speed.
- 7 February 2025Each player tracks their speed (or lack thereof) separately. Increasing your speed has no effect on whether another player has speed.