explain
SELECT * FROM t1 AS t1_outer WHERE EXISTS (
SELECT * FROM t2 WHERE i2 IN (
SELECT i3 FROM t3 INNER JOIN t1 AS t1_inner ON (t1_inner.c1 = c3 ) WHERE t1_inner.i1 < t1_outer.i1 ) );

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1_outer	ALL	NULL	NULL	NULL	NULL	5	Using where
2	DEPENDENT SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
2	DEPENDENT SUBQUERY	t3	ref	i3	i3	5	test.t2.i2	2	Start temporary; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
2	DEPENDENT SUBQUERY	t1_inner	ALL	c1	NULL	NULL	NULL	5	Using where; End temporary; Using join buffer (incremental, BNL join)