Addslots

[Forge]

Every ID can find AddSlots in Forest 2 from a box - but you don't want to hunt boxes. That's even more boring than rare enemies.

I'd suggest Redria/Yellowboze Nar Lilies in Temple Alpha. Whiteninja once told us how to find five of them at once - I think it is like this:

o Keep restarting the Temple until you start before the room with the crush traps. This may require multiple save and quits.
o Leave the crush trap room by the western exit and head north to the room with the laser fence switch. Kill all of the enemies along the way. After pressing the switch, leave that room by the eastern door.
o In this room, there'll be two Lilies over the gap, and some Dimenians. Kill the Dimenians and run back to the crush trap room - you may be able to go south, I cannot remember.
o From the crush trap room, head east and north, and kill all of the enemies in this room, press the switch to raise the bridge and return to the room where you left the two Lilies. There should now be five.
o Pipe away.

Hope this helps. Since there are five enemies, it is likely to take 103 trips...