Not sure I've thought about the full strategy for all of these, but definitely a new flavor of card here. A few thoughts:
Blood pact is a backdoor way to uber-Bless your creature spam--you would get most bang for your buck using with cheaper creatures. But since there's no restriction to
creatures as it's described, you could use this in a typical rainbow deck with your army of Skeletons. Most like playing a Graboid, evolving it and then applying Blood pact. For 3
and 1
(and the 5
), all your 1/1 creatures become 5/5!!!! So the OP potential here is great. Would probably need to restrict it to
creatures (which is what I think you were intending all along.)
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Infectoplasm is my favorite of these. Like Virus meets Antimatter, but would be more effective when played on low attack creatures since you'd get healing sooner. Antimatter for dragons, Infectoplasm for fodder. Plus since it gets better with each turn, it'd be crushing to get this out in early game play on a lowly creature (like an unprotected Otyugh!)
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Mimicat seems too complicated to be useful:
1. Draw Infectoplasm and play it
2. Activate Multiplication
3. Draw Mimicat and play it
4. Activate Mimic
Moreover, if I'm reading it right, you get an Infectoplasm back at some point after activating Mimic? That seems to be too much--like getting your Virus back after killing the opponent's creature.
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Reunion tree is a good thought, but not sure what kind of deck it's built for. You'd already need
for the Druid/Elf/Mutate, so it wouldn't help a mono
deck. The exception is the case where opponent mutates your creature--but even then, they don't use to improve your deck, and Mutate leaves 1/3 dead, 1/3 Abomination and 1/3 mutant. It eliminate the need for
with Forest Spirits, but not sure that's worth taking a space in your deck to gain the ability to use 1
instead of 1
.