Gear comes in seven tiers, from white Common to rainbow Prismatic. Higher tiers roll more stats, class-ability bonuses and unique abilities, and every roll is stronger. A tier can only drop once you've reached its organ, but combining two pieces can reach one tier beyond that.
The top tier: it rolls more stats than any other tier and cycles through rainbow colours everywhere it's shown.
7 stats (every stat an Envelope or Matrix can roll; 7 of the 8 on a Capsid, Tail Fibers or Spike Protein), 3 ability bonuses, 3 unique abilities; roll strength ×3.3
Drops from organ 8 (Brain); combining can make it from organ 7
Can't be combined any further
Dismantles for 1,200 A, 1,200 T, 800 C, 400 G (item Lv 1, +0)