MasterVolthawk, I found some error in your guide and I make some correction. The one in [] can be deleted.
Articuno: Level 53; 30%; Frosty Grotto 5F; ****; After Credit Rolls
Zapdos: Level 45; 30%; Mt. Thunder Top 3F; ****; After Credit Rolls
Moltres: Level 52; 30%; Blaze Mountain Top 3F; ****; After Credit Rolls
Mewtwo: Level 40; 99.9%; Western Cave 99F; *; After First Encounter
Mew: Level 40; 0.9%; Buried Relic 36-99F; *; Music Box needed to encounter [Only generated when the floor is created or in monster house]
Raikou: Level 45; 0.1%; Lightning Field 30F; *; After First Encounter
Entei: Level 45; 0.1%; Fiery Field 30F; *; After First Encounter
Suicune: Level 45; 0.1%; Northwind Field 30F; *; After First Encounter
Lugia: Level 30; 99.9%; Silver Trench 99F; ****
Ho-oh: Level 50; 99.9%; Mt. Faraway 40F; ****; After First Encounter
Celebi: Level 45; Joins without fight in Purity Forest 99F; *
Regirock: Level 18; 0.1%; Buried Relic 15F; *; Rock Part or Music Box needed to recruit
Regice: Level 23; 0.1%; Buried Relic 25F; *; Ice Part or Music Box needed to recruit
Registeel: Level 25; 0.1%; Buried Relic 35F; *; Steel Part or Music Box needed to recruit
Latias: Level 28; Joins in Pok�mon Square after completing Pitfall Valley; *
Latios: Level 30; Joins in Pok�mon Square after completing Pitfall Valley; **
Kyogre: Level 25; 50%; Stormy Sea 40F; ****
Groudon: Level 37; -10%; Magma Cavern Deepest Grounds 3F; ****; After Credit Rolls
Rayquaza: Level 45; -10%; Sky Tower Top 9F; ****; After First Encounter
Jirachi: Level 40; 99.9%; Wish Cave 99F; * [Wish Stone is not needed to recruit]
Deoxys: Level 35; -10%; Meteor Cave 20F; *