Cadira does not have summoning sickness, and cannot be blocked by an opponent.
You control at least five tokens.
Steps
Deal combat damage to an opponent using Cadira.
Cadira triggers, creating at least five 1/1 Rabbit creature tokens.
Activate Phyrexian Altar five times by sacrificing five Rabbits, adding ({W} magic symbol) ({U} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) .
Activate Najeela by paying ({W} magic symbol) ({U} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) , untapping all attacking creatures, giving them trample, lifelink and haste, and gaining an additional combat phase after this one.
Repeat each combat phase.
If you control six or more tokens when Cadira deals combat damage, this combo nets infinite Rabbit tokens and colored mana.