These take you from 4 mana to 6 mana, but most cubes have effects that take you from 3 mana to 6 mana like Worn Powerstone and Coalition Relic. If paying 4 mana for a mana rock, you probably are expecting it to take you to Ugin/Karn mana, like with Thran Dynamo. If playing in a very low power cube, they could work, but they're overcosted by about 2.
They are way too slow for cubes even it is for a multiplayer environment, they are too slow for even commander. A 6 mana investment to untap with 1 extra mana is a terrible rate when you consider a signet does that for 2, even if you are get 2 counters on it you are spending 8 mana and 2 turns for a 1 shot coalition relic.
If you are interested in this kind of effect I would suggest the storage lands (Fountain of Cho)or dual storage lands (Dreadship Reef). If your environment is slow enough to consider the mana batteries then it is probably slow enough to have after more lands come in tapped. These lands will give you the same effect cheaper, save a spell slot and tap for mana normally when you need it.
A playable mana battery would be pretty sweet:
1 Karn's Battery
Legendary Artifact
Karn's Battery enters the battle field tapped
Tap: Put a storage counter on Karn's Battery.
Tap, Remove any number of storage counters from Karn's Battery: Add 1 to your mana pool for each storage counter removed this way.
"... just remember, you still have to charge it"
I don't even know how strong it is but it is cheap, clean and not broken. You could maybe even cost it at 0 and make a Mox Battery.
They are way too slow for cubes even it is for a multiplayer environment, they are too slow for even commander. A 6 mana investment to untap with 1 extra mana is a terrible rate when you consider a signet does that for 2, even if you are get 2 counters on it you are spending 8 mana and 2 turns for a 1 shot coalition relic.
These tap for 1 with a 4 investment, and 2 with a 6 investment. Still not great, but they do provide mana without any counters.
They are way too slow for cubes even it is for a multiplayer environment, they are too slow for even commander. A 6 mana investment to untap with 1 extra mana is a terrible rate when you consider a signet does that for 2, even if you are get 2 counters on it you are spending 8 mana and 2 turns for a 1 shot coalition relic.
These tap for 1 with a 4 investment, and 2 with a 6 investment. Still not great, but they do provide mana without any counters.
Ah, I missed that you get the first mana free. I even reread it after your first post and still managed to miss it. It definitely makes them a lot better but I still think I prefer the lands for a "battery" effect.
I like them as cards, but unfortunately they just aren't all that good anymore. The ramp is more valuable than the storage effect, and it's hard to play a card like Blue Mana Battery over something like Sky Diamond even, and that card doesn't see play either. I think these are relegated to the old school format cubes (where even there they're questionable at best).
White Mana Battery Green Mana Battery Red Mana Battery Black Mana Battery Blue Mana Battery
I lean to multiplayer and non-powered for my cubing so any thoughts along those lines would be great.
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[180 classic cube]
If you are interested in this kind of effect I would suggest the storage lands (Fountain of Cho)or dual storage lands (Dreadship Reef). If your environment is slow enough to consider the mana batteries then it is probably slow enough to have after more lands come in tapped. These lands will give you the same effect cheaper, save a spell slot and tap for mana normally when you need it.
A playable mana battery would be pretty sweet:
I don't even know how strong it is but it is cheap, clean and not broken. You could maybe even cost it at 0 and make a Mox Battery.
These tap for 1 with a 4 investment, and 2 with a 6 investment. Still not great, but they do provide mana without any counters.
[180 classic cube]
Ah, I missed that you get the first mana free. I even reread it after your first post and still managed to miss it. It definitely makes them a lot better but I still think I prefer the lands for a "battery" effect.
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