Obsidian Fireheart
Creature — Elemental
: Put a blaze counter on target land without a blaze counter on it. For as long as that land has a blaze counter on it, it has "At the beginning of your upkeep, this land deals 1 damage to you." (The land continues to burn after this creature has left the battlefield.)
- CMC
- 4
- Mana cost
- Color identity
- R
- Rarity
- mythic
- Set
- Zendikar
- Price
- $0.83
- EDHREC rank
- #16691
Obsidian Fireheart puts a ticking clock on any land — blaze a zone, and it deals 1 damage per upkeep until the game ends, no mana required after the initial activation. Four mana for a 4/4 with that kind of inevitability is a real rate, but the three-activation cost to stick the first counter means you're investing six total mana to get the engine running, which is slow against anything proactive. Zo-Zu the Punisher decks are the natural home, where every land drop compounds the bleeding.
Best Commanders
Commanders with the highest synergy
Zo-Zu the Punisher
Zo-Zu the Punisher taxes every land entry; Obsidian Fireheart adds a persistent burn source that doesn't need players to cast spells or play lands — once a zone is blazing, the damage just happens, stacking a second damage vector on top of Zo-Zu's already punishing gameplan.
Format Analysis
Where it lives, where it can’t
| Format | Verdict |
|---|---|
| commander | legal |
| legacy | legal |
| modern | legal |
| pioneer | not legal |
| standard | not legal |
| vintage | legal |
| pauper | not legal |
| oathbreaker | legal |
Obsidian Fireheart is legal in Commander, Legacy, Modern, Vintage, and Oathbreaker, but it sees meaningful play only in Commander. In eternal formats like Legacy and Vintage, a four-mana 4/4 that deals incremental damage to a single zone is nowhere near the power threshold — those formats end games before blaze counters matter. In Commander, the multiplayer math changes the calculus: one activation can drain an opponent across ten or more upkeeps, and with three opponents at the table, you can spread blazed zones to guarantee constant chip damage through the mid-game. It's a Commander card wearing a Modern-legal frame.
Key Combos
Combo lines featuring this card
Price Context
Current price
$0.83 bulk tier
At $0.83, Obsidian Fireheart sits firmly in bulk territory and has stayed there — casual demand from Zo-Zu builds keeps it from bottoming out entirely, but there's no scarcity or competitive pull to push it higher. It's an easy pickup at this price for any red land-punishment deck.
Explore
Sources
Mentioned
Updated . Data from Scryfall, EDHREC, and Commander Spellbook.