Template:Ice Block strategy
Can be very effective as an endgame surprise and can be a clutch game saver, giving you one more guaranteed turn. A key card for Freeze Mage.
Note that Ice Block will be triggered in response to any attack (during the opponent's turn) that would deal fatal damage to the user - the user's Health will then be frozen at its current value. For this reason it is generally desirable for opponents to attempt to get the user's Health as low as possible before triggering the Ice Block. In this way, when the user loses Immune at the start of the next turn, they will have a minimum of Health remaining.
As with all Secrets, it should be noted that Ice Block will not activate on the controlling player's turn, meaning that sources of damage such as Fatigue, 
Mad Bomber or a paladin's Eye for an Eye on the mage's turn are capable of destroying the user despite the presence of an inactivated Ice Block.
Since this Secret will only trigger once your Health gets below 1, playing this card with the Ethereal Arcanist is a fairly strong mid-game combo, giving the minion continual +2/+2 boosts. 
Medivh's Valet can also consistently deal 3 damage, making both Medivh's Valet and Ice Block core cards for Secret Mage decks.
Counter-strategy
Like all secrets, Ice Block is vulnerable to Eater of Secrets, Flares, etc. To circumvent, your enemy has to do the work. Explosive Trap or other similar secrets that do reactionary Face damage help.
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