Here's my entry:
1. Fuse a Legendary Trio (Azelf, Uxie, Mesprit)
2. Free Spriting (Regirock, Gengar, Umbreon
3. Pokémon Monster Fusion (Mew, Articuno, Cyndaquil, Druddigon, Rotom)
4. Gen 5 fuse (Carracosta, Heatran, Haxorus)
5. Darkrai Recolor (Recolored as Haxorus)