Cheapest priced copy (Commander 2021): $0.49 at Card Kingdom, near mint, their price list as of .
Trudge Garden 
Enchantment · Rare · Secrets of Strixhaven Commander · #290
Whenever you gain life, you may pay {2}. If you do, create a 4/4 green Fungus Beast creature token with trample.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
3 printings · $0.49 to $1.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2021 | 69 | Rare | $0.49 | — |
| Commander 2021 | 396 | Rare | $1.99 | — |
| Secrets of Strixhaven Commander | 290 | Rare | $0.49 | — |
4 rulings from Wizards of the Coast
- 16 April 2021An ability that triggers "whenever you gain life" triggers just once for each life-gaining event, no matter how much life you gain.
- 16 April 2021You may only pay {2} once for each life gain event.
- 16 April 2021Each creature with lifelink dealing combat damage causes a separate life-gaining event. For example, if two creatures you control with lifelink deal combat damage at the same time, a "whenever you gain life" ability will trigger twice. However, if a single creature you control with lifelink deals combat damage to multiple creatures, players, and/or planeswalkers at the same time (perhaps because it has trample or was blocked by more than one creature), the ability will trigger only once.
- 16 April 2021If you gain an amount of life "for each" of something, that life is gained as one event and the ability will trigger only once.