SELECT p.id, @e := te1.damage_factor /100 * te2.damage_factor /100 AS e
FROM pokemon AS p
INNER JOIN pokemon_types AS t1 ON p.id = t1.pokemon_id
INNER JOIN type_efficacy AS te1 ON t1.type_id = te1.target_type_id
INNER JOIN pokemon_types AS t2 ON p.id = t2.pokemon_id
INNER JOIN type_efficacy AS te2 ON t2.type_id = te2.target_type_id

WHERE te1.damage_type_id =10
AND t1.slot =1
AND te2.damage_type_id =10
AND t2.slot =2
AND te1.damage_factor /100 * te2.damage_factor /100 >=2