Art by Carl CritchlowIn "one" word: Open-ended
AKA "package synergy cube"
If you're looking for simple and effective entry points - the usual aggro / control / ramp / goodstuff stuff is all well supported. However, the majority of decks will be midrange decks that combine multiple synergy packages in open-ended ways.
For more detail on that...
What is package-based synergy???A common approach to building synergy-based decks is to pick a theme and dedicate your deck entirely to that theme. This is called "linear" synergy (for some reason).
This cube deemphasizes linear synergies in favor of "package-based" ones. With this style, you combine several smaller packages into one deck. Hopefully the result is a deck that has multiple mechanical identities and yet still feels cohesive.
An example: in constructed, slivers are a highly linear strategy. Here, you might want to play a deck with only a few slivers in it. Let's say you have a sacrifice package in your deck, and you're using Dregscape Sliver as a 2-drop that can provide a body to sac on unearth. You could then add in a tiny slivers package - something like Acidic Sliver, Sliver Hive, and another random sliver or two - with only a few slots. It won't be your plan A, but each piece is fine by itself and there'll be games when they combine to do more.
Sam Black has written a lot about this style, with different terminology (he uses "clusters" similarly to "package"):
- Clusters and Building White Decks with Magic Origins
- Drafting Modern Masters 2015 - see discussions of the different ways you can draft Spirits and Artifacts synergies
- B/G/X Midrange In Standard: A Case Study In Building With Clusters
P1P1 power level tiers (0 is best, 4 is worst):
Tier 0, Tier 1, Tier 2, Tier 3, Tier 4