Depends on what you're looking for. They do different things. My thought process for r4...
1. Rank up a champ you use a lot (AW path, BG's, content) 2. Does taking them to r4 make them more useful (strong defender who can use the boost in attack or vice versa)
Personally, I'd take Serpent (which I did). Gets the added attack values and makes him even stronger on D). Thanos can still nuke everything he's supposed to at r3. He has more counters on D than Serpent does. Cool thing is, you can't go wrong either way.
Comments
defender who can be used on attack - serpent
nuke attacker who is also good defender - thanos ( one of my 3 r4s and most used by far )
1. Rank up a champ you use a lot (AW path, BG's, content)
2. Does taking them to r4 make them more useful (strong defender who can use the boost in attack or vice versa)
Personally, I'd take Serpent (which I did). Gets the added attack values and makes him even stronger on D). Thanos can still nuke everything he's supposed to at r3. He has more counters on D than Serpent does. Cool thing is, you can't go wrong either way.