SURGE FOILCheapest priced copy (Doctor Who): $0.49 at Card Kingdom, near mint, their price list as of .
Kate Stewart 
Legendary Creature — Human Scientist · 3/3 · Rare · Doctor Who · #744
Whenever you put one or more time counters on a permanent you control, create a 1/1 white Soldier creature token.
Whenever Kate Stewart attacks, you may pay {8}. If you do, attacking creatures get +X/+X until end of turn, where X is the number of time counters among permanents you control.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
4 printings · $0.49 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Doctor Who | 139 | Rare | $0.49 | $0.49 |
| Doctor Who | 422 | Rare | $0.49 | $0.49 |
| Doctor Who | 744 | Rare | — | $0.49 |
| Doctor Who | 1013 | Rare | — | $0.79 |
2 rulings from Wizards of the Coast
- 13 October 2023Similarly, its last ability counts only time counters on permanents, not on cards you own in exile.
- 13 October 2023Kate Stewart's first ability triggers only when you put time counters on permanents. It does not trigger when you put time counters on cards in exile.