Heart-Piercer Bow has its own triggered ability, which is controlled by the player who controls the Bow, no matter who controls the creature its attached to. This can be a little confusing with Act of Treason, so read up on that interaction here!
Author: bimmerbot
You can’t see face-down creature spells with Lens of Clarity.
A creature only exists on the battlefield, while a creature spell exists on the stack. As such, Lens of Clarity doesn't let you see face down spells before you decide whether to respond to them.
Ivorytusk Fortress vs. Icy Blast, Crippling Chill, et. al.
Ivorytusk Fortress tells you to untap your creatures with +1/+1 counters during your opponent's untap step, while Icy Blast and its kin say they don't untap during their *controller's* next untap step. This means there's no problem untapping during the opponent's turn!
Howl of the Horde’s Raid ability
Howl of the Horde only creates a second delayed trigger if you attacked before you cast the Howl. It doesn't make a delayed trigger automatically that checks whether you attacked later on in the turn.
Don’t forget to reveal your Morphs as a game ends!
Whenever a face-down card changes zones, you must reveal it before it actually moves. This includes as a game ends and you would shuffle it into your deck. Don't get in trouble by forgetting!
Deflecting Palm and lethal damage from combat
Deflecting Palm can pretty easily cause a game to become a draw by preventing and dealing some part of combat damage from multiple attacking creatures.
Meandering Turtle and Act of Treason
Meandering Towershell's trigger uses the wording "your control" which is distinctly different from "it's owner's control." That means it's pretty easy to take control of the Turtle permanently with thinks like Act of Treason!
Force Away on your only 4+ power creature – No looting for you.
What happens if you are saving your 4/4 from a removal spell using Force Away? Do you still get to draw and discard? Only if you also control another 4+ power creature, it turns out. Here's why.
Anafenza and tokens (they aren’t “cards”).
A token is never a card, and vice versa. Anafenza's replacement effect only applies to actual cards, so it doesn't interfere with tokens hitting the graveyard normally.