It is effective when defending Crown Towers since it will be able to affect both the defensive units and buildings.
A high risk, high reward strategy is to send out a Minion Horde, then use the rage on them. If your opponent's spells and splash units are baited, the Minion Horde can devastate their towers.
Inherently, the Rage is a high-risk, high-reward card that requires good timing in order to succeed. When using Rage, be careful to time it right or else an opposing counter attack will come unhindered due to the player's lack of Elixir.
Place it on as many troops as possible to maximize its effect.
The Rage card is very similar to the Rage Spell in Clash of Clans, except that the spell speeds up attack speed instead of damage per hit. It can also boost the spawn speed of spawner buildings like the Goblin Hut, the production rate of the Elixir Collector, and the charge speeds of the Inferno Tower and Inferno Dragon.
The Rage is the cheapest Epic card with a cost of 2 Elixir. (The Mirror can cost the same, but it doesn't have a determined cost).
Along the perimeter of the spell, symbols will light up in sequence like a clock as the spell's duration continues, and the spell fades away when they all light up.
Troops affected by the Rage will sound higher pitched.
It is tied with the Zap and The Log for the cheapest spell in the game.
It is one of only five Elixir spells from Clash of Clans to also be in Clash Royale, the others being the Lightning, Freeze, Heal and Clone.