I've been thinking on runes a bit, and while they may be a safer/more conservative first step, I think they're rather interesting.
Equipment are already a solid strategy, and offer some efficient bonuses, or further uses to low cost dorks. Being able to customize equipment, and make them even more efficient seems interesting. Now, in several cases, the question arises, "Why not just run another equipment?" Why not run
Loxodon Warhammer over
Rune of Sustenance? Having played several voltron decks, I can say that requip costs can certainly add up. I don't
know that Runes will be the answer to that, but adding trample onto a
Sword of Feast and Famine so that
Solemn Simulacrum can't chump the triggers anymore might be interesting.
Giving a
Chariot of Victory deathtouch for that First Strike and Trample goodness... That seems... good?
Runes also have interesting synergy with Vehicles. Previously, vehicles have been hard to enchant, since... well... any Enchant Creature will just fall off at EOT. But runes enchant a permanent, and are active if the permanent is a creature. This means you can now enchant and upgrade your vehicles as well.
Typically auras have the 2-1 drawback associate with them, but since each of these runes cantrips, that negates that drawback.
Would you run any of these runes, if they instead were equipment with "Equip 0"?
Does that make them good enough? I don't know. But the design is actually rather interesting, and I can see why they kept them very basic when they are upgrading already efficient cards. Especially when it comes to equipment, since they've made so many mistakes on equipment in the past.
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Also, I feel this set gave Blue the most experimentation, giving it two very powerful ramp cards in
The Omenkeel (
Cosima, God of the Voyage) and in
Orvar, the All-Form.
Then Blue also got some new removal toys in
Ravenform as a bit of a bend/break, and
Bind the Monster as a new cheap option.
Reflections of Littjara also is a powerful effect that has previously belonged in green (
Dual Nature). Blue certainly makes token copies, but ahs usually been with one shot or recurring spells.
Mystic Reflection is another new effect, that is extremely versatile and a massive play making option. While everything it does is very "blue" (token copies of creatures, or
Swan Song impersonation), it's such a bizarre effect, and so broad.