Haste all but guarantees you get the first activation once it resolves, and the 1/4 deathtouch body will discourage any opportunistic attacks while still letting you tap to rummage before your untap step
This includes mono-blue Commander decks, which often focus on this color's strengths: card draw, countermagic, bouncing permanents, and flying threats, for example
Bhaal, Lord of Murder The goad idea I mentioned last time is the right frame in which to fit Bhaal
Most of those decks need a lot of blue pips and while the double white on the threshold ability might be a lot its worth a look with all the dual lands out there
let's face it, if you're playing sea monsters, you know what you want
And the ultimate for Karn, Living Legacy creates an emblem that deals one damage to any target upon tapping an untapped Artifact you control