This is cool, I’d love to see the other colors too if you did them.
At first I thought the +2 was a bit too much for a free ”lord” and maybe it is but then again if you’re playing slivers you’re not really holding them back to block. This does really help combat though.
Another random idea: 1 split white/Phyrexian mana instead and theme them all some kind of twisted Phyrexian slivers.