On-draw effect

On-draw effects are a type of triggered effect which activate when that card is successfully drawn from the deck.

Currently, almost all on-draw effects deal damage, while many cause the card to self-destruct, and draw another card to replace it. Many cards with on-draw effects are shuffled into the opponent's deck, with negative effects once drawn.

On-draw effects are distinguished from general draw-related triggered effects, which activate when another card is drawn.

Strategy

 * Due to the nature of card draw, on-draw effects are difficult to predict or prevent. This can make it hard to plan around their useful effects, or give the player a chance to evade their drawbacks.
 * There are a few ways players can avoid activating enemy on-draw effects that have been shuffled into their decks. Tracking is particularly useful for this, neutralising any on-draw effects displayed. However, the most common way is to intentionally maintain a full hand, causing any further cards to be overdrawn. While drastic, this can be an effective strategy and in the right circumstances a desirable trade off, such as if facing lethal from a Burrowing Mine, while the opponent's hand and board are empty. This is most viable for control decks, and is especially relevant for Freeze Mages trying to prevent a Burrowing Mine from circumventing their Ice Block. More aggressively, Fel Reaver can be intentionally employed to mill the player's own deck.

Patch changes

 * Ancient Curse and Ancient Shade added.
 * Ambush and Sea Reaver added.
 * Added, with Burrowing Mine and Flame Leviathan.