Screams from Within + Gremlin Tamer: infinite mana for 26 cents

The thesis is simple: €0.26 for an infinite mana loop is a conversion rate that, in bracket 4, has no justification for being ignored.

The mechanism

The line exploits a downside that becomes an engine.

• Cast Screams from Within paying and attach it to a creature with toughness equal to 1.
• The creature dies to a state-based action: toughness at 0.
• The death trigger fires both Gremlin Tamer and Screams from Within itself (which detaches and returns to hand when the enchanted creature dies).
• Gremlin Tamer returns the dead creature to the battlefield thanks to its death trigger.
• Recast Screams from Within on the same creature (toughness 1 again), repeat the loop.

The technical point is where the infinite mana lives: if Gremlin Tamer generates mana when the creature comes back (or the creature itself does so via an ETB/death effect), each iteration of the loop produces more mana than it costs to recast the aura. The fixed cost is per cycle; if the net return is positive or equal, you have a closed loop. Always check the exact card text in your build before declaring it infinite: the combo depends on the value generated by the return, it isn't infinite "regardless."

Where to slot it in

Color identity: mono black, courtesy of Screams from Within () and Gremlin Tamer (presumably black or hybrid black-red depending on the printing — check the exact color in the listing before registering it in a deck with a tight color identity).

Coherent commanders:

• Any value-oriented mono-black commander that closes out games with drain or sacrifice payoffs: the infinite mana here serves to power outlets, not to win on its own.
• Commanders that reward creatures dying repeatedly: anything with a "whenever a creature dies" trigger scales linearly with this loop.
• Mono-black aristocrats decks: the combo is a cog in the machine, not plan A. Look for it in lists that already want low-toughness creatures to sacrifice in a loop.

Bracket note: 4 is correct. It's not a bracket 2-3 combo due to setup cost (you need a specific toughness-1 creature already on the battlefield, not always available on command), but it's not cEDH-tier either given how fragile the line is.

Protecting the line

Breaking points, in order of priority:

• Aura removal: Screams from Within is an easy target for a naturalize effect. Keep it protected or accept that it's a "one-shot" line per turn.
• Scarce toughness-1 creatures: if you don't have a target creature on the battlefield, the loop doesn't start. Include cheap enablers with native toughness 1.
• Interaction during the loop: since it's a loop of triggers and SBAs, it's vulnerable to effects that modify the creature's toughness while the loop is running (opposing anthem effects, for instance). Sequence the loop entirely within the same turn you open it — don't leave it half-finished.
• Stack discipline: make sure to resolve Gremlin Tamer's trigger before recasting the aura, otherwise you lose an iteration and waste mana.

Budget vs Premium

There's no distinction here: the combo is already at the price floor. €0.19 + €0.07 = €0.26, down 24% in two weeks. There's no "premium version" of two cards worth a few cents — the only sensible upgrade is in the support, not in the pieces themselves:

• More efficient sacrifice outlets to convert the infinite mana into a win-con.
• Protection for the aura (generic protection, granted hexproof, or simply redundancy with a second copy of the engine if it exists in another form).

The verdict

At 26 cents, this is probably the combo with the best cost-to-potential ratio in the format right now: the economic downside is zero, the gameplay downside is the aura's fragility and its dependence on a specific target. In a bracket-4 mono-black aristocrats deck, it's an automatic include. Outside that context, it's a piece worth keeping an eye on but not worth forcing.