Furnace

"The Furnace spawns two Fire Spirits at a time. It also makes great brick-oven pancakes."

Summary

 * The Furnace is unlockable from the Spell Valley (Arena 5).
 * It is a spawner building that spawns 2 Fire Spirits every 10 seconds.
 * It appears to be a cast-iron steam train furnace with a bubbling cauldron of Elixir on top of it. It is also covered various other props, including a ladder on the side of it, and a pile of firewood on the other.

Strategy

 * The Furnace can spawn up to 10 Fire Spirits over its lifetime, which would cost 6 Elixir to deploy 9 of them manually, creating a profit of 2.3 Elixir.
 * Can be used with other spawner buildings to deal high instant splash damage.
 * The Furnace is a good counter against spawner decks although ironically it's a spawner card, due to the fact that the Fire Spirits spawned deal splash damage.

Trivia

 * The Furnace was added to the game on 3/5/16 with the May Update.
 * A Balance Update on 18/5/16 decreased the Furnace's elixir cost by 4 (from 5), its hitpoints by 14% and lifetime to 40 seconds (from 50 seconds).
 * It is the second spawner to not take the appearance of a 'Hut', the first being Tombstone.
 * It seems that it has Elixir in the pot.
 * The pot on top of the Furnace resembles the Cauldron from Clash of Clans.
 * The pot on top of the Furnace jumps into the air when spawning the Fire Spirits.
 * The ladder and the stack of firewood's places on the sides on the Furnace are swapped around in game compared to the card picture.

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