Izuna's death. Tobirama or Madara?

[RasenUchihaChaos]

based on izuna's words after he got slashed on not trustign the senju because of rama attitude he gave them up willingly

 

[K1domaru]

My guess is that Izuna was going to die by the wound Tobirama made and when he saw he will not make it out he gave his eye's to Madara.